I am pleased to publish the results of my fourth HSP survey which I launched in September 2016. Many thanks are due to the 169 people who gave their time and completed the survey - this wouldn't have been possible without you. Most of the respondents were from the
The text below is a short version of the results. The full version goes into more detail on each of the different elements, with more graphs, tables and detailed breakdowns of different results and factors, and the questionnaire scoring systems. The full analysis can be found here:
https://drive.google.com/file/d/0BzEoTkR5HCWhSEQ1UElwamVod3c/view?usp=sharing&resourcekey=0-8UrNFT_UZbvcSyvprbNg9A
This analysis is by far my longest yet. Apologies for some readers, the lines on my tables are not behaving themselves this year!
These results show that the average and maximum scores are generally independent of mobility although the average score rises slightly with decreased mobility. Those who do not use mobility aids (mobility score 0 or 1) have lower minimum scores than those who use mobility aids (mobility score 2 or more).
The
factors do change with level of mobility. For those who do not need aids (mobility
score 0-1). Most people agree with “I soon become weak after physical effort” (80%
agree) and fewest agree with “The thought of having to do something often puts
me off doing it” (53% agree). At the other end of the mobility score, those in
wheelchairs all or most of the time (mobility score 8-9) most people agree with
“By the end of the day I'm shattered” and “I can become weak even if I've not
been doing anything” (93% agree with each) and fewest agree with “When I awake
in the morning, I feel unrefreshed” (70% agree).
These results show that the average and maximum scores are generally independent of mobility although there is a slight upward trend on the average score with decreased mobility. There is no clear pattern in the minimum score.
This table shows that between around 90% of people with HSP have moderate or severe fatigue.
This shows that there are people in each mobility band who do not have any bladder symptoms, and there are people within each mobility band who have bladder symptoms. Given that the score ranges between 0 and 16, for the purposes of this analysis I am grouping scores as follows;
This shows that around three fifths of people with HSP have mild bowel effects, and around one third have moderate effects. A few people have no effects at all, and no people showed severe effects. There is a general trend that the milder effects tend to be with those with lower mobility issues, and the bowel effects tend to be more severe with those with higher mobility issues.
Mobility Analysis
From the answers
to the mobility questions it is possible to see which mobility aids are the
most regularly used. Around half of respondents use walking
sticks/poles/crutches/canes, and similarly, around two fifths of respondents
use a wheelchair or mobility scooter. FES is
the mobility aid used by the least number of people, with a take-up of around
5%. Broadly these results are similar to those from previous years.
I have
devised an “HSP mobility score” which then allows me to cross-reference
mobility against the other questions in the questionnaire. The definition of
the HSP mobility score is;
- No mobility effects
- Walks without aids but has some
effects
- Orthotics/AFO/FES and/or
Sticks/Poles/Crutches/Canes some of the time
- Sticks/Poles/Crutches/Canes and
Frame/Chair some of the time
- Sticks/Poles/Crutches/Canes
most of the time
- Sticks/Poles/Crutches/Canes all
of the time
- Rollator/Walking frame most of
the time
- Rollator/Walking frame all of
the time
- Wheelchair/Mobility scooter
most of the time
- Wheelchair/Mobility scooter all
of the time
The overall results are;
Mobility Aids Used -
Overview:
|
Respondents
|
Percentage
|
Mobility Score
|
Those without aids
|
30
|
18%
|
0-1
|
Those who use mobility aids some of the time
|
42
|
25%
|
2-3
|
Those who use sticks most/all of the time
|
55
|
32%
|
4-5
|
Those who use frames most/all of the time
|
13
|
8%
|
6-7
|
Those who use chairs most/all of the time
|
29
|
17%
|
8-9
|
Fatigue
Fatigue is often noted as a symptom
of HSP. My 2013 survey showed that 62% of people experienced fatigue as a
significant symptom and 30% experienced fatigue as a minor symptom. I wanted to
find out more about fatigue.
I could
only find one paper on fatigue in HSP, a study from 2015-2016 which examined
non-motor symptoms in people with SPG4 in Brazil – Non-motor symptoms in patients with hereditary spastic paraplegia
caused by SPG4 mutations, by Katiane Servelhere and others. (https://www.ncbi.nlm.nih.gov/pubmed/26806216)
This study used the Modified Fatigue Impact Scale for fatigue and reported that
“patients with SPG4-HSP had more severe fatigue than controls (MFIS: 31.3±14.9
vs 14.9±15.4, p<0 .001="" o:p="">
There has
also been research undertaken in assessing fatigue in Multiple Sclerosis (a
common misdiagnosis for HSP) including development of the Neurological Fatigue
Index. The Brief Fatigue Inventory also appears to be used in a number of
different conditions, including cancer. Since all of these are available in a
short-form version I chose to ask all three questionnaires, and would then be
able to test if one is more suited to HSP. The questionnaire asked respondents
to complete:
- Neurological Fatigue Index (NFI-MS, a 9 question survey)
- Modified Fatigue Impact Scale
(MFIS-5, a 5 question survey)
- Brief Fatigue Inventory (BFI, a
9 question survey)
Neurological Fatigue Index - MS
The Neurological Fatigue Index (NFI-MS) asks people to select how much
they agree with each of 9 questions, selecting from; Strongly Disagree, Disagree,
Agree and Strongly Agree. The nine questions are:
·
Sometimes,
I lose my body strength
·
Sometimes,
I really have to concentrate on what are usually simple things
·
The
thought of having to do something often puts me off doing it
·
By
the end of the day I'm shattered
·
If
I've overdone things, I know about it the next day
·
I
soon become weak after physical effort
·
Resting
allows me to carry on
·
I
can become weak even if I've not been doing anything
·
When
I awake in the morning, I feel unrefreshed
Details of the survey can be found
here: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2834659/.
Each question is scored depending on the answer selected, where Strongly
Disagree =0, Disagree =1, Agree =2 and Strongly Agree =3. The overall score is
the sum over the nine questions, and therefore can range between 0 (answering
‘strongly disagree’ to all questions) and 27 (answering ‘strongly agree’ to all
questions).
The table
below shows the results.
Mobility Score
|
Respondents
|
Minimum Score
|
Average Score
|
Maximum Score
|
0-1
|
30
|
3
|
16.6
|
26
|
2-3
|
41
|
7
|
15.4
|
24
|
4-5
|
52
|
9
|
17.5
|
27
|
6-7
|
13
|
9
|
17.0
|
22
|
8-9
|
27
|
10
|
19.5
|
25
|
These results show that the average and maximum scores are generally independent of mobility although the average score rises slightly with decreased mobility. Those who do not use mobility aids (mobility score 0 or 1) have lower minimum scores than those who use mobility aids (mobility score 2 or more).
The answers to the questions allow the different fatigue factors to be examined. Overall, the three statements which
the most people agreed with were “If I've overdone things, I know about it the
next day” (81% agreeing), “Resting allows me to carry on” (79% agreeing) and “I
soon become weak after physical effort” (78% agreeing). Overall, the three
statements with he least people agreeing with were “sometimes, I really have to
concentrate on what are usually simple things” (60% agreeing), “When I awake in
the morning, I feel unrefreshed” (62% agreeing) and “I can become weak even if
I've not been doing anything” (69% agreeing).
Modified Fatigue Impact Scale 5
There are two versions of the Modified
Fatigue Impact Scale (MFIS) scale, a full questionnaire with 21 questions and a
shorter version with 5 questions. The five questions are those from the full
survey whose answers correlated most strongly with the overall 21 question
survey score. The full 21 questions on this survey are themselves a subset of
the Fatigue Impact Scale. The Modified
Fatigue Impact Scale asks people to select how often fatigue has affected them,
selecting from; Never, Rarely, Sometimes, Often and Almost Always. The five
questions are:
·
I
have been less alert
·
I
have been limited in my ability to do things away from home
·
I
have had trouble maintaining physical effort for long periods
·
I
have been less able to complete tasks that require physical effort
·
I
have had trouble concentrating
Details of both versions of the
MFIS survey can be found here (along with a number of other questionnaires
associated with Multiple Sclerosis): http://www.nationalmssociety.org/NationalMSSociety/media/MSNationalFiles/Brochures/MSQLI_-A-User-s-Manual.pdf
Each question is scored depending on the answer selected, where Never =0,
Rarely =1, Sometimes =2, Often =3 and Almost Always =4. The overall score is
the sum over the five questions, and therefore can range between 0 (answering
‘never’ to all questions) and 20 (answering ‘almost always’ to all questions).
The questions have been grouped to
cover three key areas of fatigue; Physical (the two ‘maintaining physical
effort’ questions), Cognitive (the ‘less alert’ and ‘trouble concentrating’
questions) and Psychosocial (the ‘limited in my ability’ question).
The table
below shows the results.
Mobility Score
|
Respondents
|
Minimum Score
|
Average Score
|
Maximum Score
|
0-1
|
27
|
0
|
11.0
|
20
|
2-3
|
39
|
0
|
9.7
|
17
|
4-5
|
53
|
2
|
12.7
|
19
|
6-7
|
11
|
2
|
11.9
|
19
|
8-9
|
27
|
7
|
14.1
|
18
|
These results show that the average
and maximum scores are generally independent of mobility although the average score rises slightly with decreased mobility. It is only those in
wheelchairs all or most of the time (mobility score 8 or 9) who consistently
have a higher minimum score.
The MFIS scale allows us to look at
the different areas of fatigue. The overall maximum score of 20 would comprise
a score of 8 each from Physical and Cognitive sections and a score of 4 from
the Psychosocial section, and the graph below splits the average score into the
three areas:
This graph shows that the physical
questions make the greatest contribution to the fatigue score across all levels
of mobility, scoring slightly more than the cognitive questions. The
psychosocial question contributes the least, and would still contribute the
least if its score were doubled to give it equal weight to the physical and
cognitive questions. From this, we can see that both physical and cognitive
factors play a part in the fatigue of people with HSP.
The
analysis of respondents with SPG4 shows results similar to the full dataset,
whereas those with SPG7 tend to have a higher level of fatigue.
The MFIS-5
questionnaire shows similar results to the Brazil
Brief Fatigue Inventory
The Brief Fatigue Inventory (BFI) has 2 sections. The first section
has three questions and asks people to rate their fatigue on a scale between 0
and 10 where 0 = ‘No fatigue’ and 10 = ‘As bad as you can imagine’. They are
asked to rate their fatigue right now, their usual level of fatigue and their
worst level of fatigue. They are then asked to rate how their fatigue has
interfered with six items using a scale between 0 and 10 where 0 = ‘Does not
interfere’ and 10 = ‘Completely interferes’. The six items are:
·
General
activity
·
Mood
·
Walking
ability
·
Normal
·
Relations
with other people
·
Enjoyment
of life
Details of the BFI are here: http://onlinelibrary.wiley.com/doi/10.1002/(SICI)1097-0142(19990301)85:5%3C1186::AID-CNCR24%3E3.0.CO;2-N/full.
The questionnaire is scored by taking the average of the scale score of the
nine items, and therefore can range between 0 (score 0 to all questions) and 10
(score 10 to all questions). The table
below shows the results.
Mobility Score
|
Respondents
|
Minimum Score
|
Average Score
|
Maximum Score
|
0-1
|
26
|
0.7
|
5.5
|
9.0
|
2-3
|
40
|
0.3
|
4.8
|
8.2
|
4-5
|
54
|
2.0
|
6.0
|
9.3
|
6-7
|
12
|
0.6
|
4.8
|
7.3
|
8-9
|
27
|
1.7
|
6.5
|
9.4
|
These results show that the average and maximum scores are generally independent of mobility although there is a slight upward trend on the average score with decreased mobility. There is no clear pattern in the minimum score.
The scale has been interpreted
within the previous Wiley link, and a number of different classifications are
made for mild, moderate and severe fatigue in cancer patients, as shown in
Table 4 in the link. Since the average score is unlikely to be a whole number,
I am using the following similar definitions;
·
Score
less than 3 – Mild fatigue
·
Score
between 3 and 7 – Moderate fatigue
·
Score
greater than 7 – Severe fatigue.
The table
below shows the number of respondents with mild, moderate and severe fatigue,
along with the proportion of that mobility score group:
Mobility Score
|
Respondents
|
Mild Fatigue
|
Moderate Fatigue
|
Severe Fatigue
|
0-1
|
26
|
3 (12%)
|
15 (58%)
|
8 (31%)
|
2-3
|
40
|
6 (15%)
|
31 (78%)
|
3 (8%)
|
4-5
|
54
|
6 (11%)
|
28 (52%)
|
20 (37%)
|
6-7
|
12
|
2 (17%)
|
9 (75%)
|
1 (8%)
|
8-9
|
27
|
1 (4%)
|
15 (56%)
|
11 (41%)
|
Overall
|
159
|
18 (11%)
|
98 (62%)
|
43 (27%)
|
This table shows that between around 90% of people with HSP have moderate or severe fatigue.
Fatigue Summary
Of the people which answered the
fatigue questions, 126 said that their fatigue at the time they answered the
questions was similar to their normal level of fatigue. 7 people said their
fatigue was better than normal and 36 said that their fatigue was worse than
normal. This may suggest that the results of this survey present a slightly
more adverse picture than ‘normal’ for the fatigue levels of people with HSP.
166 respondents answered the
question about which fatigue survey they preferred. 132 said that they had no
clear preference for one of the surveys. Of the 34 respondents who expressed a
preference 19 preferred the NFI questionnaire, 9 preferred the MFIS-5
questionnaire and 6 preferred the BFI questionnaire. There were people from
across the range of mobility scores who preferred the NFI and MFIS-5
questionnaires. Whereas people who preferred the BFI tended to have less
reliance on mobility aids, with mobility scores between 1 and 5.
The average scores for each of the
three fatigue questionnaires show that fatigue is generally independent of
mobility. Those respondents who do not use mobility aids tended to score
slightly lower fatigue levels than those who use mobility aids all or most of
the time, but there is a wide spread of data, and there are some who do not use
mobility aids who have higher levels of fatigue than those who use mobility
aids all the time.
The MFIS-5 questionnaire shows that
whilst the physical factors of HSP contribute the most to fatigue there is also
an important cognitive aspect. Those with SPG7 tend to have a higher level of
fatigue than those with SPG4. The BFI questionnaire shows that around 90% of
people with HSP have moderate or severe fatigue.
Bladder Issues
There have been a number of papers
examining bladder issues in those with HSP. Bladder
dysfunction in hereditary spastic paraplegia: a clinical and urodynamic
evaluation, by Fourtassi et al in 2012 (Pubmed ID 22289900), reports
urgency being the most common complaint affecting 72% of people, followed by
increased frequency (affecting 66%), incontinence (affecting 55%) and hesitancy
(affecting 52%). The study examined 29 patients and was carried out in France Estonia
The various texts on HSP often
describe having overactive bladders (OAB). I reviewed different short form
questionnaires for overactive bladders, and found the International
Consultation on Incontinence Modular Questionnaire (ICIQ). There are a number
of different questionnaires for different aspects of different pelvic problems,
and they have the objective of developing validated international standard
questionnaires for wide use.
They have an overactive bladder
survey http://www.iciq.net/ICIQ.OABmodule.html
which “provides a brief and robust measure to assess the impact of symptoms of
overactive bladder on quality of life and outcome of treatment.” There are four
questions in this questionnaire, and users select their answers from
pre-determined answers.
The scale does not appear to show
what a normal score would be. However, this report (http://bmcurol.biomedcentral.com/articles/10.1186/s12894-015-0009-6)
uses the questionnaire to examine stress levels within a population with
overactive bladders, carried out by Henri Lai (et al) in St Louis , USA
Of note, that paper reports that “OAB
patients reported psychological stress levels that were …. significantly higher
than healthy controls. There was a positive correlation between perceived
stress levels and urinary incontinence symptoms, and its impacts on quality of
life among OAB patients.”
Overall score
These
questions were answered by 165 respondents. The following table gives a summary
of the results;
Mobility Score
|
Respondents
|
Minimum Score
|
Average Score
|
Maximum Score
|
0-1
|
30
|
0
|
5.4
|
10
|
2-3
|
41
|
0
|
4.4
|
14
|
4-5
|
53
|
0
|
5.6
|
12
|
6-7
|
13
|
0
|
7.5
|
14
|
8-9
|
28
|
1
|
7.1
|
16
|
Overall
|
165
|
0
|
4.6
|
16
|
This shows that there are people in each mobility band who do not have any bladder symptoms, and there are people within each mobility band who have bladder symptoms. Given that the score ranges between 0 and 16, for the purposes of this analysis I am grouping scores as follows;
·
3-6
= mild effects, things occur “occasionally”,
·
7-10
= moderate effects – things occur “some of the time”
·
At
least 11 = severe effects – things occur “most” or “all” of the time.
Using this
scoring system the results show:
Mobility Score
|
Respondents
|
No effects
|
Mild effects
|
Moderate effects
|
Severe effects
|
0-1
|
30
|
5 (17%)
|
14 (47%)
|
11 (37%)
|
0 (0%)
|
2-3
|
41
|
14 (34%)
|
17 (41%)
|
8 (20%)
|
2 (5%)
|
4-5
|
53
|
9 (17%)
|
29 (55%)
|
11 (21%)
|
4 (8%)
|
6-7
|
13
|
1 (8%)
|
4 (31%)
|
8 (38%)
|
3 (23%)
|
8-9
|
28
|
5 (18%)
|
9 (32%)
|
8 (29%)
|
6 (21%)
|
Overall
|
165
|
34 (21%)
|
73 (44%)
|
43 (26%)
|
15 (9%)
|
This shows that around two thirds
of people with HSP have no or mild bladder effects, and around one third have
moderate or severe effects. There is a general trend that the milder effects
tend to be with those with lower mobility issues, and the bladder effects tend
to be more severe with those with higher mobility issues.
The results
of the bladder questions appear to be broadly in line with two previous studies
examining bladder issues in people with HSP, from France
and Estonia
·
The
key bladder symptoms appear to be frequency and incontinence, affecting the
greatest proportion of respondents.
·
Passing
urine 4 to 6 times per day is normal. Just under half of respondents do this, just
over half go more often.
·
Passing
urine no more than once a night is normal, two thirds of respondents do this, one
third go more often.
·
A
third of respondents have to rush to the toilet most or all of the time, with a
further quarter having to rush sometimes. Two fifths do not have to rush.
·
Urine
leakage most or all of the time occurs in one fifth of respondents, a further third
have this sometimes. Overall, half of respondents are affected by incontinence,
one fifth of respondents are not affected and three tenths are affected
occasionally.
·
The
level of bother is generally above that expected by symptoms. Many respondents
are bothered quite a lot by these symptoms.
Bowel Issues
There do not appear to be any
papers examining bowel issues in those with HSP. Several reports describe bowel
or sphincter issues, but from the abstracts available none appear to quantify
this.
When reviewing
the short form questionnaires for overactive bladders I noted the International
Consultation on Incontinence Modular Questionnaire (ICIQ) included a
questionnaire on the bowel. The website http://www.iciq.net/structure.html
indicates that the bowel surveys are not finalised, however there are several
other references to the ICIQ-B survey, e.g. https://www.kingstonmaternity.org.uk/media/187024/bowl-function-questionnaire-iciq-b-uk-english-.pdf.
There are twenty two questions in
this questionnaire, with users selecting their answers from pre-determined
lists. I decided that I would ask nine of these questions in order to get a
picture of bowel function, following the general format of the overactive
bladder questionnaire. The questions I selected were:
·
Q3A/3B:
On average how many times do you open your bowels in 24 hours?
·
Q4:
How often do you open your bowels during the night from going to bed to sleep until
you get up in the morning?
·
Q5:
Do you have to rush to the toilet when you need to open your bowels?
·
Q6:
Do you use medications (tablets or liquids) to stop you opening your bowels?
·
Q7:
Do you experience pain/soreness around your back passage?
·
Q8:
Do you experience any staining of your underwear or need to wear pads because of
your bowels?
·
Q13:
Do you have bowel accidents when you have no need to open your bowels?
·
Q16:
Do you need to strain to open your bowels?
·
Q23:
Overall, how much do your bowels interfere with your everyday life?
Overall score
These questions were answered by
155 respondents. The following table gives a summary of the results;
Mobility Score
|
Respondents
|
Minimum Score
|
Average Score
|
Maximum Score
|
0-1
|
28
|
2
|
8.6
|
16
|
2-3
|
39
|
4
|
8.0
|
15
|
4-5
|
51
|
4
|
9.8
|
20
|
6-7
|
11
|
5
|
10.4
|
16
|
8-9
|
26
|
5
|
11.8
|
19
|
Overall
|
155
|
2
|
9.5
|
20
|
This shows that there are people in
each mobility band who have no symptoms or minor symptoms, and there are people
within each mobility band who have several symptoms. The minimum and average
scores both generally increase as mobility issues increase. Given that the
score ranges between 2 and 37, for the purposes of this analysis I am grouping
bowel scores as follows;
·
5-11
= mild effects – things occur “rarely”
·
12-20
= moderate effects – things occur “some of the time”
·
At
least 21 = severe effects – things occur “most” or “all” of the time
Using this scoring system the
results show:
Mobility Score
|
Respondents
|
No effects
|
Mild effects
|
Moderate effects
|
Severe effects
|
0-1
|
28
|
5 (18%)
|
15 (54%)
|
8 (29%)
|
0 (0%)
|
2-3
|
39
|
3 (8%)
|
29 (74%)
|
7 (18%)
|
0 (0%)
|
4-5
|
51
|
2 (4%)
|
32 (63%)
|
17 (33%)
|
0 (0%)
|
6-7
|
11
|
0 (0%)
|
8 (73%)
|
3 (27%)
|
0 (0%)
|
8-9
|
26
|
0 (0%)
|
12 (46%)
|
14 (54%)
|
0 (0%)
|
Overall
|
155
|
10 (6%)
|
96 (62%)
|
49 (32%)
|
0 (0%)
|
This shows that around three fifths of people with HSP have mild bowel effects, and around one third have moderate effects. A few people have no effects at all, and no people showed severe effects. There is a general trend that the milder effects tend to be with those with lower mobility issues, and the bowel effects tend to be more severe with those with higher mobility issues.
·
The
key bowel symptoms are urgency and hesitancy, affecting the greatest proportion
of respondents.
·
Opening
your bowels between three times a week and three times a day is normal. 95% of
respondents do this, 5% go more often.
·
It
is not normal to open your bowels during the night. Nearly 90% of respondents
do this, almost 10% need to go in the night.
·
A
sixth of respondents have to rush to the toilet most or all of the time, with a
further third having to rush sometimes. Half do not have to rush.
·
A
third of people with HSP have to strain to open their bowels most or all of the
time, with a further third having to strain sometimes. One third do not need to
strain.
· Some people have to both rush to the
toilet and strain. 6 respondents have to rush and strain all or most
of the time.
·
Wearing
pads and/or staining underwear more than once a month occurs in about a quarter
of respondents. Less than three fifths of respondents do not have this problem,
and less than one fifth have this less than once a month.
·
One
fifth of respondents have bowel accidents ‘sometimes’ of which only a small
number have this ‘most of the time’ or ‘always’. More than half do not have
this problem, and a quarter have it rarely.
·
The
level of bother generally increases in line with symptoms. Those with more
symptoms tend to have higher levels of bother.
HSP Information Sources
I also
asked respondents where they got their information on HSP. 160 people gave
answers to these questions, although some answers were partial. Most people get
their information about HSP from social media, doctors and neurologists.
Medical websites, support groups, physiotherapists and friends/family with HSP
form another important group of information sources.
The sources
which people regarded as most trustworthy were neurologists, support groups and
physiotherapists. Social Media and friends/family with HSP form another
important group. Of sources used by more than half of respondents, the ones
with people being most unsure were doctors and other medical professionals.
Overall;
people need to be selective in what they believe on social media – and check
out the author. Support groups can be a good source of information. People may
need to work on relationships with doctors so they understand people’s
situations better. Talking about your situation with friends/family with HSP
may be useful for you and them.
Like this? in previous years:
Overview of all my surveys: http://hspjourney.blogspot.co.uk/p/my-on-line-resarch.html
2015: Modifications at home, depression, quality of life: http://hspjourney.blogspot.co.uk/2016/02/2015-survey-results.html
2014: Medication, exercise & relaxation: http://hspjourney.blogspot.co.uk/2015/02/2014-survey-results.html
2013: Symptoms and misdiagnosis: http://hspjourney.blogspot.co.uk/2014/02/hsp-survey-results.html
Like this? in previous years:
Overview of all my surveys: http://hspjourney.blogspot.co.uk/p/my-on-line-resarch.html
2015: Modifications at home, depression, quality of life: http://hspjourney.blogspot.co.uk/2016/02/2015-survey-results.html
2014: Medication, exercise & relaxation: http://hspjourney.blogspot.co.uk/2015/02/2014-survey-results.html
2013: Symptoms and misdiagnosis: http://hspjourney.blogspot.co.uk/2014/02/hsp-survey-results.html
