# Area-level factors influencing geographical distribution of myopia prevalence among school-aged children and adolescents in Northwest China

## TL;DR

The study finds that myopia rates in school-aged children in Northwest China vary greatly between regions, likely due to socioeconomic and environmental factors.

## Contribution

The study identifies area-level socioeconomic and geo-environmental factors as key drivers of myopia prevalence in Northwest China.

## Key findings

- Myopia prevalence is higher in northern Xinjiang (56.9%) compared to southern Xinjiang (42.2%).
- Area-level factors like economic income and environmental greening are linked to myopia prevalence.
- Myopia prevalence ranges from 65.1% in Karamay to 24.1% in Hotan.

## Abstract

Northwest China is an ideal spot to investigate geographic differences in myopia prevalence due to the region’s unequal allocation of socioeconomic and geo-environmental variables. Yet, the overall geographic distribution of myopia in the region remains unclear.

We conducted a school-based, cross-sectional prevalence survey of myopia in all 14 prefectures of Xinjiang, China. We employed Moran's I index to quantify the spatial distribution of myopia prevalence. We conducted correlation and multivariate logistic regression analyses to determine the independent association of socioeconomic and geo-environmental factors with myopia.

We included a total of 64 277 Han (36.6%), Uygur (38.1%), and other ethnic groups (25.3%) children and adolescents aged 6–18 years. The overall myopia prevalence was 52.2%, with northern areas (56.9%) showing a substantially greater prevalence than southern areas (42.2%). Myopia prevalence varies widely between regions, ranging from 65.1% (Karamay, located in northern Xinjiang) to 24.1% (Hotan in southern Xinjiang), and a spatial aggregation of myopia prevalence was identified (Moran's I = 0.364; P = 0.090; Z-score = 1.696). Rather than variations in latitude, the geographical distribution of myopia prevalence may be influenced by disparities in area-level socioeconomic factors (e.g. economic income and health care coverage) and geo-environmental factors (e.g. sunshine duration and environmental greening).

There are notable differences in the prevalence of myopia in children and adolescents between northern and southern Xinjiang of northwest China, where socioeconomic circumstances and geo-environmental factors differ greatly. The influencing factors identified in our study may be key area-level intervention targets for myopia control in public health policy.