The adequacy of domiciliary non-invasive positive pressure ventilation (NIHV) for hypercapnic restrictive pulmonary disease in patients aged 75 years or above has been questioned, because of a lower life expectancy, a higher risk of neuropsychological impairment and a lower potential for adapting to NIHV. This study aims to illustrate that the use of NIHV is possible and efficient in this age group. In our referral area, all patients under NIHV have been included in a database since 1994; at the end of 1996, all patients in whom NIHV had been initiated at age 75 years or above were studied. We performed a cross-sectional study of six patients (two men, four women, age: 79 +/- 3 years at time of study) who had been under NIHV for 31 +/- 17 months. Patients underwent pulmonary function testing, assessment of respiratory muscle strength, physical disability and neuropsychological performance, tolerance and compliance to NIHV, and health-related quality of life (SF-36, St. George Respiratory Questionnaire: SGRQ). Hospitalization rates were recorded for the year prior and the 2 yr following initiation of NIHV. By the time of the study, all patients showed improved arterial blood gases when compared to values before NIHV (PaCO2: 46 +/- 9 vs 66 +/- 10 mmHg, P = 0.04). Patients adapted well to NIHV, with minor side-effects and an average daily use of ventilator of 10.5 +/- 2 h. None of the patients showed signs of emotional disturbance. SF-36 scores for mental health, subjective well-being and vitality, or social functioning, did not differ from that of age-matched controls. SGRQ scores were similar to those published for younger patients under NIHV. Use of health care facilities was similar to that of younger patients under NIHV; hospitalization rates decreased significantly after initiating NIHV (40 +/- 31 days for year before NIHV, vs 13 +/- 14 days and 0.8 +/- 0.4 days for the 2 yr following NIHV, P = 0.02). Age above 75 years should not be considered per se as a contraindication to NIHV in patients with well-accepted indications for this treatment. Our results suggest that in this age group, the cost/benefit ratio of NIHV may be favourable.