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Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
user
Reid index in increased in ?
assistant
The correct answer is  Ans. is 'a' i.e., Chronic bronchitis The Reid Index is a mathematical relationship that exists in a human bronchus section observed under the microscope. It is defined as ratio between the thickness of the submucosal mucus secreting glands and the thickness between the epithelium and cailage that covers the bronchi. A normal Reid Index should be smaller than 0.4, the thickness of the wall is always more than double the thickness of the glands it contains. Chronic smoking causes submucosal gland hyperophy and hyperplasia, leading to a Reid Index of > 0.5 indicating chronic bronchitis