Rationale

Obesity is associated with pulmonary arterial hypertension (PAH), but its impact on outcomes such as health-related quality of life (HRQoL), hospitalizations and survival is not well understood.

Objectives

To assess the effect of obesity on health-related quality of life (HRQoL), hospitalizations and survival in patients with PAH.

Methods

We performed a cohort study of adults with PAH from the Pulmonary Hypertension Association Registry, a prospective multicenter registry. Multivariate linear mixed effects regression was used to examine the relationship between weight categories and HRQoL using the Short Form-12 (SF-12) and emPHasis-10 (e10). We used multivariable negative binomial regression to estimate hospitalization incidence rate ratios (IRRs) and Cox regression to estimate hazard ratios (HRs) for transplant-free survival by weight status.

Results

767 subjects were included: mean age of 57 years, 74% female, 33% overweight and 40% obese, with median follow-up duration of 527 days. Overweight and obese patients had higher baseline e10 scores (worse HRQoL), which persisted over time (p<0.001). The overweight and obese have a trend towards increased incidence of hospitalizations compared to normal weight (IRR 1.34, 95% confidence interval (95%CI) 0.94-1.92 and 1.33, 95%CI 0.93-1.89, respectively). Overweight and obese patients had lower risk of transplant or death as compared to normal weight patients (HR 0.45, 95%CI 0.25-0.80 and 0.39, 95%CI 0.22-0.70, respectively).

Conclusions

In a large multicenter, prospective cohort of PAH, overweight and obese patients had worse disease-specific HRQoL despite better transplant-free survival compared to normal weight patients. Future interventions should address the specific needs of these patients.