Impact of quality of life related to foot problems: a case–control study

Abstract

Foot problems are highly prevalent conditions, being a frequent reason for medical and podiatric consultation. The aim of this study was to compare the differences of quality of life (QoL) related to foot health in people with and without the presence of foot problems. A case–control study was carried out in an outpatient centre, where a clinician recorded data related to sociodemographic and clinical characteristics. In addition, self-reported data on foot health-related quality of life were recorded using the Spanish version of the Foot Health Status Questionnaire. The sample consisted of 498 participants (249 cases and 249 controls), with a median age of 30 years and an interquartile range of 23 years. The differences between the groups were statistically significant for gender, age, footwear, general health, foot health, and physical activity. Cases showed lower scores for the domain of footwear, physical activity and vitality compared to controls. Foot pathologies have a negative impact on quality of life related to foot health, and the domains of footwear, general health and physical activity seem to be the factors that are associated with the presence of alterations and foot deformities.

Full text

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
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Impact of quality of life related
to foot problems: a case–control
study
Daniel López‑López1,2*, Mónica Pérez‑Ríos1,3, Alberto Ruano‑Ravina1,3, Marta
Elena Losa‑Iglesias4, Ricardo Becerro‑de‑Bengoa‑Vallejo5, Carlos Romero‑Morales6,
Cesar Calvo‑Lobo5 & Emmanuel Navarro‑Flores7
Foot problems are highly prevalent conditions, being a frequent reason for medical and podiatric
consultation. The aim of this study was to compare the dierences of quality of life (QoL) related
to foot health in people with and without the presence of foot problems. A case–control study was
carried out in an outpatient centre, where a clinician recorded data related to sociodemographic
and clinical characteristics. In addition, self‑reported data on foot health‑related quality of life were
recorded using the Spanish version of the Foot Health Status Questionnaire. The sample consisted
of 498 participants (249 cases and 249 controls), with a median age of 30 years and an interquartile
range of 23 years. The dierences between the groups were statistically signicant for gender, age,
footwear, general health, foot health, and physical activity. Cases showed lower scores for the domain
of footwear, physical activity and vitality compared to controls. Foot pathologies have a negative
impact on quality of life related to foot health, and the domains of footwear, general health and
physical activity seem to be the factors that are associated with the presence of alterations and foot
deformities.
e feet are an essential foundation of people’s health, and due to their complex anatomical characteristics, they
play a key role in posture and ambulation, since they are responsible for the autonomy, independence and well-
being of the individual. Currently, there is an increase in the prevalence of foot pathologies, ranging between 61
and 79%, which is why they constitute an important public health problem1,2. In addition, there are other factors,
such as the diculty in managing foot problems, in part due to their multifactorial aetiology, the discomfort they
can cause, and the high demand regarding these complaints by patients2,3, that could result in their chronicity.
Moreover, the non-existence of two identical cases among people who suer from them should be underlined,
as they are determined by a specic diagnosis, and the characteristics of the structures involved, whether they
are: ligamentous, muscular, bone, vascular and/or nervous4,5, producing an increase in health spending and a
worsening of established cases. us, foot problems can reduce quality of life, lead to loss of balance, make it
dicult to put on shoes, and increase the risk of falling6–8. All of this can aect activities of daily living, includ-
ing the desire to go outside.
Despite the importance of foot pathologies, both due to their prevalence and their impact on activities of daily
living, there are few studies in Spain that have measured the inuence of quality of life in these patients compared
to healthy subjects and, specically, which facets of quality of life could be most aected by these pathologies9–11.
e objective of this study was to compare quality of life related to foot health in people with and without
the presence of foot problems.
OPEN
Departamento de Medicina Preventiva e Saúde Pública, Facultad de Medicina e Odontoloxía, Santiago de
Compostela, Spain. Grupo de Investigación Saúde e Podoloxía, Departamento de Ciencias da Saúde, Facultade de
CIBER
de Epidemiología y Salud Pública, CIBERESP, Madrid, Spain. Faculty of Health Sciences, Universidad Rey Juan
Carlos, Alcorcón, Spain. School of Nursing, Physiotherapy and Podiatry, Universidad Complutense de Madrid,
Madrid, Spain. Faculty of Sport Sciences, Universidad Europea de Madrid, Villaviciosa de Odón, Madrid,
Spain. Department of Nursing, Faculty of Nursing and Podiatry, Frailty Research Organized Group, Universidad de
Valencia, Valencia, Spain. *email: daniellopez@udc.es
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Material and methods
Design and sample. is is a case–control study carried out in a private podiatry centre providing foot
health care services, in the city of A Coruña (Galicia, Spain), between January 2016 and December 2017. e
selection of study participants was carried out through non-random sampling and the recommendations for
the communication of observational studies, known as Strengthening the Reporting of Observational Studies in
Epidemiology (STROBE)12, were followed.
e inclusion criteria for the group of cases were established as interest in participating and completing the
study phases. e exclusion criteria were the following: immunosuppressed people, people with the presence
of systemic conditions, a history of surgery and / or orthopaedic treatments on the feet, lack of partial or total
autonomy in daily activities, as well as those who did not want to sign the consent form or did not understand
the instructions to participate in the research. In the group of controls, the inclusion criteria were the following:
people who attended for a health check on their feet, who did not present any problems with them and who
completed all phases of the investigation. Regarding the exclusion criteria of the control group, they were related
to: presenting foot pathologies, drug use, presenting any systemic disease or inability to carry out the research.
All participants had a median age of 30years, an interquartile range of 23years, with no upper age limit, and
there were no criteria established by gender. All subjects signed the informed consent to be included in the study.
Calculation of the sample size. e sample size required for this case–control study, with specic levels
of condence, power, and groups of equal size was calculated through the Epidat version 4.2 programme (Con-
sellería de Sanidade, Xunta de Galicia, Spain; Organización Panamericana de la salud (OPS-OMS); Universidad
CES, Colombia).
A total sample size of 498 subjects (249 per group) was determined assuming a condence level of 95%, a
power of 0.80, an odds ratio to detect of 2.0 and an expected proportion of exposed of 88.268%, and in the con-
trols of 79%. e actual sample (total of 498 participants) consisted of 249 cases (15 men and 234 women) and
249 controls (45 men and 204 women).
is research was approved by the Research Ethics Committee of the University of Coruña, with le number
CE 010/2015. All participants were informed about the procedures used in this study to give and sign their
informed consent. Additionally, the guidelines associated with the ethical standards for investigation and experi-
mentation in people as reported in the Declaration of Helsinki, in their last modication and others internationals
institutionals organisations bodies were preserved.
Procedure. In the rst place, an experienced clinician with more than ten years’ providing attention to the
treatment of foot pathologies, recorded the general health status of each patient, the anthropometric variables
(age, sex, body mass index), the medical and surgical history, the presence of systemic diseases and current
medication.
Second, a physical examination of the general state of the health of the feet was carried out by means of struc-
tural assessment using palpation, analysis of joint mobility and tests of muscle strength in the foot. In addition,
the clinical history of each patient was accessed to verify any other foot pathology and / or chronic diseases, as
well as complementary tests (ultrasound and X-rays).
ird, for the evaluation of the impact of quality of life related to foot health, each patient anonymously self-
administered the Foot Health Status Questionnaire, in its Spanish version13. is tool contains three sections.
e rst section presents a high degree of validity related to the content, the evaluation criteria and the construct
of the four specic domains to analyse foot health associated with: foot function, foot pain, footwear and condi-
tion of foot health, with a Cronbach’s alpha of 0.89–0.95, and high retest reliability with an intraclass correlation
coecient of 0.74–0.9214. e second section was validated and adapted from the Medical Outcomes Study
36-Item Short-Form Health Survey and presents four domains for the assessment of general health, physical
function, social function, and nally vitality15,16. e third section contains the record of the sociodemographic
characteristics corresponding to the clinical history of each participant16. Once the third phase was completed
by the patient, the clinician recorded the information from each questionnaire using the FHSQ soware (version
1.03). is programme provides the nal score for each dimension in a range from 0 to 100, with zero identifying
the worst state of health and 100 an optimal state of health.
Statistical analysis. e anthropometric variables (age, sex, body mass index) and the independent vari-
ables were presented as mean and standard deviation (SD) and with the ranges of maximum and minimum val-
ues. Regarding the categorical variables, they were presented with absolute values and with percentages. Fisher’s
exact test was used to test the dierences in the frequencies of the levels of categorical variables (sex) between the
groups with and without foot pathologies, while the independent sample t-test was used to test the dierences
between the two groups in the form of continuous variables (age, height, weight, BMI, foot pain, foot function,
footwear, foot health, general health, physical activity, social function, vitality). Dierences were considered sig-
nicant when the p value < 0.05. A multivariate logistic regression was performed to predict the case or control
status based on the scores of the items on the scale considered. For this, and to have greater power, each item
was divided into two categories, using the median as the cut-o point and considering the category with the best
result as the reference category. Results were adjusted for sex, age, and BMI and are provided as ORs with 95%
condence intervals. Data were processed with the statistical package IBM SPSS Statistics version 25.
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Results
A total of 498 participants completed the investigation, 249 cases and the same number of controls. Regarding the
age distribution of the sample, it ranged from 15 to 69years, with a median age of 30years, and an interquartile
range of 23. e sample included 88% of women. e composition of the sample can be seen in Table1.
Regarding the results on quality of life related to foot health among the group of cases and controls, they are
shown in Table2. ese scores were higher for the control group, in the rst section for the footwear domain and
lower for foot pain, foot function, and overall foot health. In the second section, they obtained higher scores in
the domains of physical activity and vitality and lower scores in the domains of general health and social capacity.
e dierences between the groups were statistically signicant for footwear and general health and there
were no signicant dierences for the dimensions of the questionnaire that assessed foot pain, foot function,
general foot health, physical activity, social capacity and vitality.
Table3 shows the multivariate logistic regression, where it can be observed that those people who had worse
scores on the scale items related to footwear, physical activity, foot health and vitality, had a higher probability
of being a case. is association was greater for footwear (OR 4.470 (IC95% 2.569–7.775)) followed by physical
activity. However, general health showed a negative association with the probability of being a case or a control.
Discussion
e results of this research show that people with foot pathologies have a worse quality of life than the general
population. is is observed with the assessment of the items on the scale used, both globally and individually.
e analysis of the individual items showed that the people with the worst scores in the use of footwear were up
to 4 times more likely to have foot pathologies compared to controls. To our knowledge, this is the rst study to
analyse the quality of life of Spanish patients using the Foot Health Status Questionnaire, in its Spanish version.
e reason for carrying out this study is the high prevalence of foot pathologies in Europe, as reected by
Burzykowski etal. in a multicentre project involving 70,497 patients who presented ranges of 56 to 64% of various
Table 1. Comparison of demographic characteristics of the total sample, patients with foot problems and
controls. BMI body mass index, SD standard deviation.
Total group
Mean ± SD
Range
(n = 498)
Cases
Mean ± SD
Range
(n = 249)
Controls
Mean ± SD
Range
(n = 249)
Weight (kg) 67.02 ± 14.18
(40–121) 65.04 ± 13.97
(40–121) 69.01 ± 14.15
(43–120)
Height (cm) 1.65 ± 0.08
(1.50–1.98) 1.64 ± 0.07
(1.50–1.93) 1.66 ± 0.08
(1.50–1.98)
BMI (kg/m2)24.64 ± 4.78
(16.80–43.51) 24.17 ± 4.84
(16.80–43.18) 25.11 ± 4.68
(17.30–43.51)
Sex (%)
Male 60 (12%) 15 (6%) 45 (18.1%)
Female 438 (88%) 234 (94%) 204 (81.9%)
Table 2. Comparison of FHSQ scores of the total sample, patients with foot problems and controls.
† Median ± IR (range) and Mann–Whitney U test were utilised. In all the analyses, p < .05 (with a 95%
condence interval) was considered statistically signicant.
Total Group
(n = 498) Cases
(n = 249) Controls
(n = 249) p value
Foot pain 76.81 ± 19.75
(0–100) 78.36 ± 19.07
(0–100) 75.25 ± 20.32
(0–100) .082†
Foot function 82.68 ± 19.52
(0–100) 82.99 ± 18.24
(6.25–100) 82.36 ± 20.76
(0–100) .763†
Footwear 47.20 ± 30.84
(0–100) 42.03 ± 31.99
(0–100) 52.37 ± 28.77
(0–100) .000†
General foot health 56.05 ± 24.92
(0–100) 57.66 ± 23.65
(0–100) 54.44 ± 26.08
(0–100) .329†
General health 68.02 ± 22.95
(0–100) 79.50 ± 30.00
(10–100) 56.55 ± 19.96
(0–100) .000†
Physical activity 84.52 ± 20.59
(5.56–100) 84.26 ± 20.47
(5.56–100) 84.79 ± 20.74
(5.56–100) .221†
Social capacity 78.82 ± 24.33
(0–100) 82.52 ± 20.06
(0–100) 75.11 ± 27.50
(0–100) .025†
Vitality 54.73 ± 23.25
(0–100) 53.32 ± 25.28
(0–100) 56.14 ± 20.99
(0–100) .048†
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pathologies in the feet with and without infection, where they conrm that early diagnosis prevents long-term
structural or infectious sequelae, morbidity and cost associated with foot care17. In addition, several existing
studies indicate lower satisfaction in quality of life related to foot health in people diagnosed with foot problems
and the presence of systemic diseases18–23.
However, based on our knowledge, there is a lack of studies that analyse the quality of life related to foot
health in the general population diagnosed with foot problems without the presence of associated risk factors
and without the presence of other systemic diseases that may inuence the negative impact on general health
and specically on the foot. In this way, the ndings of our study are the rst to reveal that foot pathologies in
people who do not have systemic diseases negatively inuence quality of life compared to a group of healthy
people, presenting lower scores in the domain related to footwear.
ese data are consistent with previous studies conducted at dierent stages of life that reect the negative
impact of quality of life and its relationship with the feet8,24–26.
For this reason, regular visits to the doctor and podiatrist are key aspects for improving foot health and health
at a general level, being a predictor factor in optimising health spending and contributing to the improvement
of systemic diseases, which individuals can present at dierent stages of life8,27.
In addition, the study shows how people with foot pathologies record a lower value in the footwear domain
score, which is measured specically in the rst section of the questionnaire and is consistent with the prospective
study carried out by Bennet etal. that evaluated the quality of life related to foot health in a 6-month prospec-
tive study conducted in a sample of 140 people with foot pathologies, with a mean age of 48.3years, before and
aer undergoing surgery on the foot28. Gilheany etal. in a prospective study in 122 patients with a mean age of
48years, who attended the pre-surgical consultation for presenting hallux valgus and hallux rigidus, showed low
values in the footwear domain, coinciding with the results of our investigation29.
Regarding the second section of the questionnaire, the dimensions of vitality and physical activity are lower
in the case group, as is the case–control study carried out by López-López etal. in a sample of 150 patients with
a mean age of 49.5years with keratotic foot problems30. e case–control study carried out by Irving etal. in 94
patients, with a mean age of 52.3years with chronic pain in the heel, showed similar results in the case group to
those obtained in our study6.
ere are several limitations to this study. e main one consists of having selected controls who attended
the same podiatric clinic. It is likely that if controls from some other location had been included, the dierences
would have been greater, because although the controls did not have foot pathologies, they could have had them
recently or they could have been worried about having them and therefore have decided to go to the clinic even
Table 3. Factors that aect the presence of pathologies in the feet according to the items of the scale used.
*Adjusted Odds Ratio by sex, age and BMI. (1) Poor Health Status. *e median value has been used for the
cut o points.
Variables of the equation* Odds ratio*
(95% IC) p value
Foot pain (1)
0–81.25 1 .86
> 81.25 .619 (.359–1.070)
Foot function (1)
0–87.5 1 .387
> 87.5 1.284 (.729–2.263)
Footwear (1)
0–50.00 1 .000
> 50 4.470 (2.569–7.775)
General foot health (1)
0–60 1 .042
> 60 1.902 (1.024–3.535)
General Health (1)
0–70 1 .000
> 70 .040 (.022–.073)
Physical activity (1)
0–94 1 .000
> 94 3.281 (1.803- 5.970)
Social Capacity (1)
0–87.50 1 .735
> 87.50 1.100 (.632–1.917)
Vitality (1)
0–50 1 .020
> 50 1.850 (1.103—3.104)
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though they were healthy. Another limitation resides in having carried out the research in a single clinic, since
some external validity is subtracted from the results obtained. Future studies should include a larger number
of participating centres. In addition, case and control groups were not matched-paired by sex, age nor BMI, the
multivariate logistic regression was adjusted for sex, age, and BMI and were provided as ORs with 95% con-
dence intervals.
Among the advantages is the fact of having used a validated questionnaire to collect data on foot problems
and quality of life, which makes it possible to use a reliable measuring instrument and also to be able to compare
the results obtained with those of other investigations that have used the same questionnaire. Another additional
advantage is the relatively high number of patients included, almost half a thousand, which allows obtaining
relatively reliable estimates. e fact of having comparable subjects in terms of sex and age is also an advantage,
since the observed dierences will not be explained by imbalances in these variables.
Finally, the results presented in this research highlight the need to continue investigating the impact caused
by alterations and deformities of the feet on quality of life, with the aim of optimising therapeutic interventions
related to the feet prescribed by podiatrists and doctors in search of improvements in people’s health, well-being
and autonomy.
Conclusions
Foot problems have a negative impact on quality of life related to foot health, where the domains of footwear,
general health and physical activity seem to be the factors that are associated with the presence of alterations
and deformities in the feet.
Received: 21 January 2021; Accepted: 1 July 2021
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Author contributions
Conceptualization (M.P.-R., D.L.-L., E.N.-F., M.E.L.-I., R.B.-d.-B.-V., C.R.-R., C.C.-L., A.R.-R.); Data curation
(D.L.-L.); Formal analysis (M.P.-R., D.L.-L., E.N.-F., M.E.L.-I., R.B.-d.-B.-V., C.R.-R., C.C.-L., A.R.-R.); Investiga-
tion (M.P.-R., D.L.-L., E.N.-F., M.E.L.-I., R.B.-d.-B.-V., C.R.-R., C.C.-L., A.R.-R.); Methodology (M.P.-R., D.L.-L.,
E.N.-F., M.E.L.-I., R.B.-d.-B.-V., C.R.-R., C.C.-L., A.R.-R.); Soware (M.E.L.-I., R.B.-d.-B.-V.); Results (M.P.-R.,
D.L.-L., E.N.-F., M.E.L.-I., R.B.-d.-B.-V., C.R.-R., C.C.-L., A.R.-R.); Supervision (M.P.-R., D.L.-L., E.N.-F., M.E.L.-
I., R.B.-d.-B.-V., C.R.-R., C.C.-L., A.R.-R.); Writing—original dra preparation (M.P.-R., D.L.-L., A.R.-R.) and
Writing—review and editing (M.P.-R., D.L.-L., E.N.-F., M.E.L.-I., R.B.-d.-B.-V., C.R.-R., C.C.-L., A.R.-R.).
Competing interests
e authors declare no competing interests.
Additional information
Correspondence and requests for materials should be addressed to D.L.-L.
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