Aneesh K.V.1
BACKGROUND
Obstructive sleep apnoea (OSA) is characterised by recurrent episodes of upper airway obstructions during sleep. Recent studies suggest that OSA is independently associated with hypertension. So, the current study was done to analyse the relationship between OSA and blood pressure changes and to determine as to what extent OSA is independently contributing to those changes. This was to highlight the importance of the need for early diagnosis and prompt treatment of patients with OSA.
METHODS
97 patients with symptoms of OSA were selected. Following polysomnography, patients were grouped into two: OSA patients with Apnoea-Hypopnea Index (AHI) ≥ 5 and controls (AHI < 5). Linear regression analysis was done to find out the independent effect of exposure variables (age, body mass index (BMI), AHI etc.) on the outcome the variable (blood pressure).
RESULTS
Systolic BP was significantly high in OSA patients (154.84 ± 15.89) compared to control group (132.00 ± 11.45). Diastolic BP was significantly high in OSA patients (90.63 ± 7.87) compared to control group (85.13 ± 5.95). Linear regression analysis showed that for each unit change in AHI, systolic blood pressure changed by 0.406 independent of other factors and for each unit change in desaturation index, diastolic blood pressure changed by 0.111 independent of other factors.
CONCLUSIONS
The blood pressure levels both systolic and diastolic were significantly elevated in patients with OSA. Increase in AHI was independently associated with increase in systolic blood pressure and the increase in desaturation index was independently associated with increase in diastolic blood pressure. Since OSA is a highly prevalent and highly underdiagnosed condition, the current study emphasises the importance of screening for OSA, so that with early diagnosis and prompt treatment the development and progression of cardiovascular risk factors like hypertension can be reduced.
