Changes in self-reported impairments over 10 years in people with late effects of polio and associated factors: A longitudinal cohort study

Abstract

Background

Many people ageing with late effects of polio (LEoP) experience new or increased impairments which could negatively influence daily life. Currently, there is limited knowledge how LEoP-related impairments change over time.

Objectives

To assess how various self-reported impairments change over 10 years among people with LEoP, and explore factors associated with the changes.

Methods

This is a longitudinal cohort study, in which 181 people with LEoP (mean age 77 [SD 9] years, 99 women) responded to a postal survey twice, 10 years apart. The survey included questions on demographics, clinical characteristics, and self-reported impairments as assessed with the Self-reported Impairments in Persons with late effects of Polio (SIPP) scale. The SIPP comprises 13 items and asks how much participants have been bothered by various LEoP-related impairments during the past 2 weeks. Changes in SIPP scores were analyzed by paired sample t-test. Factors associated with the changes in SIPP total scores were analyzed with univariable linear regression analyses.

Results

Seven items in the SIPP increased significantly over the 10 years (P < 0.05): muscle weakness, muscle fatigue, sensory disturbances, breathing difficulties at rest and during physical activity, cold intolerance, and general fatigue (corresponding to 1–12%). The SIPP total score increased on average 1.64 points (CI, 0.88 - 2.41, P < 0.001), corresponding to 6%. Two variables were significantly associated with the change in SIPP total score: self-reported degree of LEoP-related disability (B = 2.96, 95% CI, 0.88–5.03; P = 0.006) and presence of co-morbidities (B = 1.72, 95% CI, 0.14–3.30; P = 0.033).

Conclusions

Impairments following LEoP seem to increase over a 10-year period but to a small degree. Having moderate to severe LEoP-related disability and comorbidities are associated with increased impairments. These findings can be accommodated in follow-ups and when providing and developing person-centered interventions for people with LEoP.