A Multidisciplinary Approach to Obesity Hypoventilation Syndrome: From Diagnosis to Long-Term Management-A Narrative Review.

Obesity Hypoventilation Syndrome (OHS), also known as Pickwickian syndrome, is a complex disorder characterized by obesity (BMI > 30 kg/m), daytime hypercapnia (PaCO ≥ 45 mmHg), and sleep-disordered breathing, primarily affecting individuals with severe obesity. Its diagnosis requires the exclusion of other causes of alveolar hypoventilation and involves comprehensive assessments, including clinical history, physical examination, pulmonary function tests, arterial blood gases, and sleep studies. The pathophysiology of OHS involves mechanical constraints from excessive adipose tissue, diminished central respiratory drive often linked to leptin resistance, mitochondrial dysfunction, and oxidative stress, all contributing to impaired ventilation and systemic inflammation. The condition often coexists with obstructive sleep apnea (OSA), exacerbating nocturnal hypoxia and hypercapnia, which can lead to severe cardiopulmonary complications such as pulmonary hypertension and right-sided heart failure. Epidemiologically, the rising global prevalence of obesity correlates with an increased incidence of OHS, yet underdiagnosis remains a significant challenge, often resulting in critical presentations like acute hypercapnic respiratory failure. Management primarily centers on non-invasive ventilation modalities like CPAP and BiPAP, with an emphasis on individualized treatment plans, continuous monitoring, and addressing comorbidities such as hypertension and diabetes. Pharmacological interventions are still evolving, focusing on supportive care and metabolic regulation. Long-term adherence, psychological factors, and complications like ventilator failure or device intolerance highlight the need for ongoing multidisciplinary management. Overall, advancing our understanding of OHS's multifactorial mechanisms and optimizing tailored therapeutic strategies are crucial for improving patient outcomes and reducing mortality associated with this increasingly prevalent syndrome.