Analysis of the prevalence and its influencing factors of diffuse goiter in Zhejiang

OBJECTIVE: To evaluate the status of diffuse goiter of population in Zhejiang Province and to analyze the relevant influencing factors. METHODS: A total of 18 188 subjects were recruited in the cross sectional survey, by multistage stratified cluster random sampling method. B ultrasound measurement were carried among the subjects to detect the thyroid volume, and the basic information and life styles were interviewed by questionnaires. Then, we analyzed the distribution and its influencing factors of diffuse goiter. RESULTS: The ratio of diffuse goiter among the surveyed population was 2.2% (403/18 188), the difference showed statistical significance (χ(2) = 267.11, P < 0.05). The ratio among the group aged 6-7 years old and 8-10 years old was comparatively high, separately 10.3% (27/262) and 9.8% (51/519). The ratio among women (2.9%, 305/10 470) was higher than it among men (1.3%, 97/7672) (χ(2) = 55.55, P < 0.05). The residents from inland areas had the highest prevalence (3.2%, 138/4374), followed by residents from sub-coastal areas (2.0%, 131/6411), coastal areas minimum (1.8%, 138/4374) (χ(2) = 24.31, P < 0.05). The content of water iodine and salt iodine among people with symptoms of goiter had statistical difference with it among ordinary population (water iodine:χ(2) = 4.95, P = 0.026; salt iodine: χ(2) = 11.03, P < 0.01). The median(quartile) of water iodine in ordinary population was 2.41 (1.96-6.15) µg/L and among people with symptoms of goiter was 1.88 (1.49-5.15) µg/L. The median(quartile) of salt iodine in ordinary population was 30.18 (24.69-32.65) mg/kg and among people with symptoms of goiter was 29.1 (24.70-31.95) mg/kg. The influential factors of goiter were as follows: the family income, the education degree, the job and profession status, the diet character, the habitual sea food consumption, the alcohol intake status (χ(2) were separately 8.08, 37.85, 98.78, 68.69, 10.91, 12.21, 26.94, P < 0.05). Multi-factor analysis showed the results as follows: female (OR = 0.27 95%CI:0.18-0.39), school students (OR = 8.05, 95%CI:3.87-16.73), vegetarian (OR = 1.60, 95%CI:1.15-2.22) took a higher risk of getting pathogenic goiter; while the group of those who had university degree or above (OR = 0.84, 95%CI: 0.73-0.97), ate sea food frequently (OR = 0.62, 95%CI:0.44-0.88) took a lower risk. CONCLUSIONS: The ratio of diffuse goiter in the group aged among 6-7 years old and 8-10 years old was comparatively high. The ratio was influenced by many factors.