N. K. Senthilnathan1, L. Muthumani2, D. Nehru3
BACKGROUND Diabetes mellitus is a metabolic disorder affecting almost all the organs by its micro and macrovascular complications. Like other organs the respiratory system is also affected by diabetic complications like microangiopathy. Very few studies investigated the complications and the relationship with the duration of the diabetes and glycaemic status. So in this point of view, we planned to study the effect of pulmonary function in our type 2 diabetic patients.
AIMS AND OBJECTIVES
To study the influence of glycaemic control (based on HbA1c levels) on pulmonary function tests and the correlation between spirometric abnormalities and duration of diabetes in type 2 diabetic patients.
MATERIALS AND METHODS
55 type 2 diabetic patients who gave informed consent were recruited. History regarding duration of diabetes, treatment, history suggestive of complications like neuropathy, retinopathy, nephropathy, regular sugar monitoring, exercise, etc. were recorded. BMI was calculated. Chest x-ray was taken for all patients. They underwent spirometry and the predicted and measured values of FEV1, FVC, FEV1/FVC, PEFR, FEF 25-75 for all the patients were recorded. After spirometry, HbA1c estimation was done using ion exchange resin method. Oneway ANOVA, correlation, paired and unpaired-t-test were used for analysis.
RESULTS
There was significant difference between the mean predicted FVC, FEV1, PEFR, and FEF 25-75, and measured values. The mean of measured spirometric values decreases as the HbA1c increases. There was reducing trend of the spirometric values as HbA1c increases, this was not statistically significant. The incidence of restrictive pattern was more common among the male patients compared with female patients but this was not statistically significant.
DISCUSSION AND CONCLUSION:
Restrictive pattern was more with increase in duration of diabetes. Out of 55 patients, 33 had probable restriction, 5 had moderate obstruction and 1 had severe obstruction. This may be due to underlying obstructive airway disease and they might have concealed smoking or other history which may attribute to obstruction. Our studies show that increase in HbA1c % values were associated with reduced spirometric values.
