Abstract Body (Do not enter title and authors here): Background
Pulmonary hypertension (PH) is a progressive condition of elevated pulmonary arterial pressure leading to right ventricular dysfunction and reduced exercise capacity. Inspiratory muscle training (IMT) is a non-pharmacological intervention to enhance respiratory strength and exercise tolerance in PH, though its impact on cardiopulmonary outcomes remains unclear.
Methods
A comprehensive literature search was conducted across PubMed, Embase, Scopus, and Cochrane from inception till April 27, 2025. Continuous outcomes were reported as mean differences (MD) with 95% confidence intervals (CI) using a random-effects model with heterogeneity assessed using I2 and chi-square statistics. All the calculations were performed in RevMan 5.4. A p-value of <0.05 was indicative of statistical significance.
Results
This meta-analysis included 5 studies involving 104 patients with a mean age of 53.16 ± 14.65 years suffering from PH with a statistically significant increase in maximal inspiratory (MD = 20.59, 95% CI: 13.26-27.91, P = 0.00001, I2 = 61%) and expiratory pressures (MD = 11.22, 95% CI: 4.79-17.45, P = 0.0006, I2 = 28%) with no difference in FEV1 (MD = -1.32, 95% CI: -4.95-2.31, P = 0.48, I2 = 0%), FVC (MD = 1.56, 95% CI: -2.29-5.41, P = 0.43, I2 = 0%), and FEV1/FVC ratio (MD = 0.68, 95% CI: -3.02-4.38, P = 0.72, I2 = 0%). There was a statistically significant increase in 6-minute walk distance (MD=48.59, 95% CI: 29.49-67.70, P<0.00001, I2=29%) with no difference in maximal heart rate (MD=-4.16, 95% CI:-11.30 to 2.98, P=0.25, I2=0%).
Conclusion
Inspiratory muscle training significantly improves inspiratory and expiratory pressures and 6-minute walk distance in pulmonary hypertension patients, with no notable effects on FEV1, FVC, or maximal heart rate. Further studies with larger samples and longer follow-up are needed to confirm these findings and assess long-term significance.