OBJECTIVE

To study health-related quality of life (HRQL) in a clinically selected sample obese outpatients.

DESIGN

A single-strand before and after study with 2-y follow-up after treatment comprising 10 weeks on very-low-energy diet (VLED) and 4 months of behaviour modification in groups.

SUBJECTS

A total of 126 patients (mean (s.d.) age 48.2 (11.1) y and body mass index (BMI) 42.8 (6.2) kg/m(2) (63% women)) referred for treatment in an obesity clinic.

MEASUREMENTS

Weight and HRQL using questionnaires (RAND 36-Item Health Survey 1.0 and Obesity-related Psychosocial problems-scale).

RESULTS

In all, 100 patients (61% women) completed the treatment and 67 (71% women) completed the 2-y follow-up. The mean (s.d.) weight loss was 12.5 (5.6)% at the end of group therapy, 6.0 (7.1)% at 1 y, and 2.6 (7.5)% at 2 y. At baseline, the mean (s.d.) score for OP-scale was 61.9 (24.6). The mean scores on every RAND-36 scale were markedly lower than in the Finns without chronic conditions. All the scales in HRQL improved markedly during the treatment. During the follow-up, all the scales started to return back towards baseline levels and at 2 y, only obesity-related psychosocial problems and physical functioning were still improved relative to baseline. In categories of weight change at 2 y (> or =10% weight loss, 0-9.9% weight loss, weight gain), obesity-related psychosocial functioning, physical functioning, and general health showed dose-response improvement with increasing weight loss. A > or =10% weight loss at 2 y after treatment was associated with clear improvement in obesity-related psychosocial problems, physical functioning, physical role functioning, bodily pain, general health, mental health, and vitality. A 0-9.9% weight loss was associated with improvement in obesity-related psychosocial problems and physical functioning. Weight gain was associated with improvement in obesity-related psychosocial problems and social functioning. The study population was too small to examine possible gender differences.

CONCLUSIONS

Treatment with VLED and behaviour modification produces marked short-term weight loss and clear improvement in all aspects of HRQL. At 2 y after treatment, the average maintained weight loss is modest. However, one-third of patients maintain > or =5% weight loss. Improvement in obesity-related psychosocial problems and physical functioning is associated even with &<10% of maintained weight loss. Since the pattern of HRQL changes did only partly follow the pattern of weight change as expected, other factors, such as the therapeutic effect of participating in the weight loss programme or increase in physical activity, may affect HRQL responses.