[Influence of lifestyle, biological and other factors on subjective evaluation of physical functioning]

To assess the strength of relationship between various lifestyle, biological, psychosocial factors, chronic conditions, pain and subjective physical performance, evaluated by "Physical functioning" scale from "Rand-36 Health Survey" questionnaire.

We used a standardized generic health related quality of life questionnaire. The study population was based on the original sample, formerly explored during the study, carried out by the Department of Propedeutics to Internal Medicine. It enroled 575 primary care patients from seven small towns located in Kaunas region. The effect exerted by various factors on ratings of subjective physical performance was evaluated by means of multiple logistic regression. Ratings of the "Pain" scale, as well as subjective rating of change in health during preceding year were included in the analysis.

The biggest influence on rating of physical functioning was exerted by reported deterioration in health during preceding year and severity of pain. Among biological factors, age, diastolic blood pressure (>80 mmHg), body mass index (> or =35) and FEV1 (%) were adversely related to subjective ratings of physical health. Smoking status, chronic respiratory conditions, disablement group, perceived lack of social support, reported shortage of food expenditures and being pensioned off, all remained significant predictors of worsened physical functioning.

Perceived physical health is affected by both objective biological and subjective factors related to the history of disease as well as psychosocial factors. These should be taken into account when planning clinical trials where health-related quality of life is intended to be analyzed among outcomes of interest.