Strabismus has a reported prevalence of 0.8% to 4.6% in children ages 6-72 months and 1.2% to 6.8% in children ages 6-17 years.[2]Sprunger DT, Lambert SR, Hercinovic A, et al. Esotropia and exotropia preferred practice pattern®. Ophthalmology. 2023 Mar;130(3):P179-221.
https://www.doi.org/10.1016/j.ophtha.2022.11.002
http://www.ncbi.nlm.nih.gov/pubmed/36526451?tool=bestpractice.com
However, the epidemiology shows marked geographic variation.
In Western populations, esotropia is the most prevalent form, whereas in Asian populations, exotropia predominates. US population-based studies have found an annual incidence per 100,000 population of 64 in exotropia (corresponding to a prevalence of 1% of children ages <11 years), 111 in esotropia (corresponding to a prevalence of 2% of children ages <6 years), and 12.9 in hypertropia (corresponding to a prevalence of 0.26% of children ages <19 years).[3]Govindan M, Mohney BG, Diehl NN, et al. Incidence and types of childhood exotropia: a population-based study. Ophthalmology. 2005 Jan;112(1):104-8.
http://www.ncbi.nlm.nih.gov/pubmed/15629828?tool=bestpractice.com
[4]Greenberg AE, Mohney BG, Diehl NN, et al. Incidence and types of childhood esotropia: a population-based study. Ophthalmology. 2007 Jan;114(1):170-4.
http://www.ncbi.nlm.nih.gov/pubmed/17070595?tool=bestpractice.com
[5]Tollefson MM, Mohney BG, Diehl NN, et al. Incidence and types of childhood hypertropia: a population-based study. Ophthalmology. 2006 Jul;113(7):1142-5.
http://www.ncbi.nlm.nih.gov/pubmed/16647125?tool=bestpractice.com
In the US, the incidence of esotropia is highest in children younger than 7 years, whereas the incidence of exotropia is highest in children ages 2-3 years and 6-9 years, and is also high in adults with sensory strabismus. The incidence of hypertropia is more evenly distributed.[5]Tollefson MM, Mohney BG, Diehl NN, et al. Incidence and types of childhood hypertropia: a population-based study. Ophthalmology. 2006 Jul;113(7):1142-5.
http://www.ncbi.nlm.nih.gov/pubmed/16647125?tool=bestpractice.com
A study from Hong Kong revealed that 27.4% of strabismic patients had esotropia, and 65.2% had exotropia (two-thirds of whom had intermittent exotropia).[6]Yu CB, Fan DS, Wong VW, et al. Changing patterns of strabismus: a decade of experience in Hong Kong. Br J Ophthalmol. 2002 Aug;86(8):854-6.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1771235
http://www.ncbi.nlm.nih.gov/pubmed/12140202?tool=bestpractice.com
The prevalence of strabismus is higher in those with intellectual disabilities (44.1%), low birth weight, and retinopathy of prematurity compared with the general population.[7]van Splunder J, Stilma JS, Bernsen RM, et al. Prevalence of ocular diagnoses found on screening 1539 adults with intellectual disabilities. Ophthalmology. 2004 Aug;111(8):1457-63.
http://www.ncbi.nlm.nih.gov/pubmed/15288971?tool=bestpractice.com
[8]O'Connor AR, Stephenson T, Johnson A, et al. Long-term ophthalmic outcome of low birth weight children with and without retinopathy of prematurity. Pediatrics. 2002 Jan;109(1):12-8.
http://www.ncbi.nlm.nih.gov/pubmed/11773536?tool=bestpractice.com
The prevalence in white people is 2% to 4%, but it may be lower in Asian populations.[3]Govindan M, Mohney BG, Diehl NN, et al. Incidence and types of childhood exotropia: a population-based study. Ophthalmology. 2005 Jan;112(1):104-8.
http://www.ncbi.nlm.nih.gov/pubmed/15629828?tool=bestpractice.com
[4]Greenberg AE, Mohney BG, Diehl NN, et al. Incidence and types of childhood esotropia: a population-based study. Ophthalmology. 2007 Jan;114(1):170-4.
http://www.ncbi.nlm.nih.gov/pubmed/17070595?tool=bestpractice.com
[5]Tollefson MM, Mohney BG, Diehl NN, et al. Incidence and types of childhood hypertropia: a population-based study. Ophthalmology. 2006 Jul;113(7):1142-5.
http://www.ncbi.nlm.nih.gov/pubmed/16647125?tool=bestpractice.com
[9]Mohney BG. Common forms of childhood strabismus in an incidence cohort. Am J Ophthalmol. 2007 Sep;144(3):465-7.
http://www.ncbi.nlm.nih.gov/pubmed/17765436?tool=bestpractice.com
[10]Matsuo T, Matsuo C. The prevalence of strabismus and amblyopia in Japanese elementary school children. Ophthalmic Epidemiol. 2005 Feb;12(1):31-6.
http://www.ncbi.nlm.nih.gov/pubmed/15848918?tool=bestpractice.com