High Salt Intake and Risk of Chronic Bronchitis: The Copenhagen Male Study—A 10-Year Followup

Table 1

Baseline characteristics (1976) of men with high self-assessed salt intake (high salt preference) and others.

	High salt intake^#	Others
Subjects  𝑛	701	2169
Age yrs	53.0 ± 5.1	52.9 ± 5.1
Smoking
Current smoking	68.8	60.6^##
Smoking 1970/71	74.6	65.5^##
Alcohol use
Alcohol, beverages/week
0–5	51.2	60.6
6–20	39.8	33.8^##
21+	9.1	5.6
Occupational dust and fumes exposure	27.1	21.7^##
Other characteristics
Low social class (IV/V)	52.6	50.2
Lower airway symptoms
Do you cough when you wake up in the morning?
% yes	13.8	11.9
In wintertime do you cough many times during the day or at night?
% yes	10.2	8.1^+
Do you cough many times a day or during the night for a period of more than three months per year?
% yes	6.7	5.4
In wintertime do you cough up phlegm when you wake up in the morning?
% yes	18.4	15.7^+
Do you cough up phlegm during the night or during the day for a period of more than three months per year?
% yes	6.1	5.6

Data are presented as mean ± SD or percentages. ^#: high salt preference; ⁺: 𝑃<0.10; ^##: 𝑃<0.01; 𝑃 value of Chi-squared test or unpaired t-test (age).