Headache is one of the most commonly encountered complaints in Ophthalmology outpatient department.1 Headache (HA) is defined as pain located in the head, above the orbitomeatal line and/or nuchal ridge.2The estimated global prevalence of active headache disorder was approximately 52.0%.3 The International Headache Society classifies headache broadly as primary headache, secondary headache, neuropathies, facial pains and other headaches.2Headache can be due to a variety of ocular causes like refractive errors, convergence insufficiency, acute angle closure glaucoma, uveitis, optic neuritis, and accommodative spasm.4Headache associated with refractive errors play a significant role.5 The prevalence of refractive errors ranges from 13 to 80% in different studies.6,7Refractive errors, commonly hypermetropia, astigmatism and myopia lead to visual impairment.8They may cause headache of varying duration and severity. Headache due to refractive errors impacts the quality of life.9 .Refractive errors that are not corrected often lead to headaches in the frontal or occipital regions.10Spasms or fatigue of the ciliary muscles is one possible cause of headache in individuals with refractive errors.11Headache attributed to refractive errors has to meet the following diagnostic criteria according to IHS Cephalgia (headache) is attributable to uncompensated or suboptimally corrected ametropia (unilateral or bilateral) when at least two of the following criteria are met: • Ametropia's manifestation or progression is temporally correlated with the onset or exacerbation of cephalgia. • Significant cephalgia amelioration subsequent to optical correction. • Cephalgia exacerbation during prolonged visuomotor tasks at compromised visual acuity. • Abatement of cephalgia upon cessation of the visuomotor task.2 The current study is thus undertaken to investigate the correlation between refractive errors and headache in the patients attending Ophthalmology OPD at a Medical College.

A Hospital based, prospective, cross sectional study was conducted in the Department of Ophthalmology, GVPIHC&MT, Visakhapatnam for 3 months. 300 patients were enrolled in the study after applying the requisite criteria. The Institutional Ethics Committee approval was taken. Informed and written consent was obtained from all patients after duly explaining the purpose of the study and procedure to be followed. Patients who presented with chief complaint of headache were included in the study after applying the requisite inclusion and exclusion criteria. Inclusion criteria : Patients presenting with headache to the Ophthalmology outpatient department were included in the study. Exclusion criteria: Patients below the age of 18 years and above 35 years were excluded in the study. Patients with anterior segment or posterior segment pathology like cataract, pseudophakia, aphakia, uveitis, glaucoma, optic neuritis were excluded. Other possible causes of headache as outlined by the International Headache Society were excluded by detailed history elicited. Patients who were not willing to take part in the study. • The patient’s demographic data was noted. • A detailed history included the onset ,duration, location, progression, frequency of attacks, duration of attacks ,severity of pain ,nature of pain regarding headache were noted. any exacerbating and relieving factors, diurnal or seasonal variation was noted. • Other associated complaints like blurring of vision, eye pain, nausea, vomiting, photophobia, phonophobia was detailed. • Relevant past history, personal history was taken. • Visual Acuity was assessed with standard Snellen’s chart at a distance of 6m. Improvement with pinhole is noted for. • Automated refraction with autorefractometer (Potec PRK 5000) and subjective verification was done on all patients. • Cycloplegic refraction after instilling tropicamide 1% drop each in both eyes every 15min for 3 times was done with autorefractometer. • Post mydriatic test was performed to determine the final subjective refraction. The specific classifications of ametropia, encompassing spherical refractive errors (myopia and hyperopia) and astigmatic components, along with their respective dioptric magnitudes, were documented. • Any heterophoria was screened for by cover, uncover test. • The Anterior Segment examination was done under slit lamp biomicroscopy. Ocular fundus was evaluated by indirect ophthalmoscopy. • Any organic lesions in the anterior and posterior segment was excluded from the study.The patients were followed up for 1 month to evaluate for symptomatic relief. The data from the study was statistically analyzed using SPSS software.

A total of 300 patients were enrolled in the study. Greatest number of subjects fell in the age group of 25 to 30(39%),followed by 18 to 25 age group(31.66%),and 30 to 35 age group(29.34%). Table 1. Age wise distribution of the subjects Age group Number Percentage 18-25 95 31.66 25-30 117 39 30-35 88 29.34 Table 2. Gender wise distribution of the subjects Gender Number Percentage Male 93 31 Female 207 69 About 69% of the subjects were females and 31% were males. Table 3. Occupation of the subjects Occupation Number Percentage Students 77 25.66 Housewives 74 24.67 Teachers 45 15 Technical Personnel 43 14.34 Tailors 31 10.33 Others 30 10 The majority of the subjects were students(25.66%), followed by housewives(24.67%),teachers(15%),technical personnel(14.34%),tailors(10.33%). All of them presented with headache of less than 1 year duration. The most common site of headache was the frontal area in about 52% of subjects. 42 patients also presented with other ocular symptoms like eye strain, watering, redness, photophobia, twitching of eyes. Table 4.Location of headache in subjects Region Number Percentage Frontal 157 52.33 Occipital 54 18 Diffuse 89 29.67 Refractive errors were identified in 105 of them among 300 subjects.(35%) The most common refractive error was found to be astigmatism followed by simple hypermetropia and simple myopia. Simple myopic astigmatism was found to be the most common type of astigmatism. Table 5.Distribution Of refractive errors Refractive error Number Percentage Simple myopia 23 21.90 Simple hypermetropia 37 35.23 Simple myopic astigmatism 19 18.09 Compound myopic astigmatism 14 13.33 Simple hypermetropic astigmatism 6 5.71 Compound hypermetropic astigmatism 2 1.90 Mixed astigmatism 4 3.80 Among the 105 patients who had refractive errors, all of them were prescribed glasses with the appropriate dioptric power and followed up after one month. 73 patients reported decrease or resoution of headache, decreased eyestrain, blurring of vision and heaviness of eyes. Table 6. Symptomatic relief after glasses correction Refractive error Patients n=105 (100%) Symptomatic relief n=73 (69.5%) Simple myopia 23(21.9%) 5(21.7%) Simple hypermetropia 37(35.23%) 34(91.8%) Simple myopic astigmatism 19(18.09%) 15(78.94%) Compound myopic astigmatism 14(13.33%) 11(78.57%) Simple hypermetropic astigmatism 6(5.71%) 3(50%) Compound hypermetropic astigmatism 2(1.9%) 2(100%) Mixed astigmatism 4(3.8%) 3(75%) Table 7. Final dioptric power correction Dioptric power Frequency Less than 1D 56(53.3%) 1.5 to 2D 29(27.6%) More than 2D 20(19.04%)

In our study, the age group most commonly presenting with headache was between 25 to 30 years.(39%)In a study by Supriya et al12,the most common age group was found to be 16 to 30 years(43.3%).In a study by Inchara et al,1341.4% of the patients belonged to the 16-30yrs age group. Rajeev Kumar et al14 reported 46.66% of their patients fell in the 16 to 30 age group. Possible causes could be due to prolonged use of digital devices like mobile phones, tablets and laptops for educational and recreational purposes. In our study females(69%) outnumbered males.(31%).In a study by Supriya et al,1272% of the patients were females. In a study by Marasini S et al,1563% of the patients were females. Similar observations were seen in a study by Saba faruqui et al,16patients presenting with headache were predominantly women (75.4%)compared to men (24.5%) and in a study by Inchara N et al,13 333(66.6%) were female, and 167(33.4%) were males. The higher number of females presenting with headache maybe attributed to hormonal variations, greater amounts of psychological stress and physical stress. Most of them were students(25.66%) and housewives(24.67%) similar to findings by Supriya N et al,12Pranisha singh et al 17and Rajeev Kumar et al.14 Frontal headache was reported in 52.33% and occipital headache in 18%. Rajeev Kumar et al 14 reported frontal headache in 238 patients and occipital headache in 40 patients. Saba faruqui et al 16reported frontal headache(38.9%) to be the most common location of headache. Frontal region is the most common location for headache associated with refractive errors. In our study, out of the 300 patients who presented with headache,105 patients had refractive errors.(35%).This is similar to a study by Srimathy A Jain et al,18who reported 28% that patients were found to have refractive errors. In a study by Marasini S et al,15 44% of patients were found to have refractive errors. In the current study, the most common refractive error was astigmatism(42.85%),followed by simple hypermetropia(35.23%) and simple myopia.(21.9%).In a study by Supriya et al12 astigmatism(43.6%) is found to be the most common refractive error followed by hypermetropia(37.3%).Rajeev Kumar et al14 reported 164 patients with astigmatism and 132 patients with hypermetropia in their study. Sutapa et al reported 62% of astigmatism, followed by 31.03% of hypermetropia and 20.69% of myopia among the refractive errors.In studies by Sanjay marasini et al,15Pranisha et al ,17Siddiqui AA 19 and Vinod dhiman et al20,astigmatism was reported to be the most common refractive error. In the current study among astigmatic errors, Simple myopic astigmatism(18.09%) was found to be the most common followed by Compound myopic astigmatism(13.33%),simple hypermetropic astigmatism (5.71%),Mixed astigmatism(3.8%) and Compound hypermetropic astigmatism(1.9%).In a study by Vinod dhiman et al20,Simple myopic astigmatism, Compound myopic astigmatism, simple hypermetropic astigmatism were the most frequent astigmatic types in that order.In a study by Pranisha et al17 simple myopic astigmatism and Compound myopic astigmatism was found in majority of the patients accounting for 22.8% and 12.9% respectively. Rajeev Kumar et al 14noted 66 patients with simple myopic astigmatism,as the most common astigmatic variety. Similar finding was observed in Srimathy A Jain et al,18with simple myopic astigmatism dominating with 37.2% of patients. Final dioptric correction was less than 1D in 53.3% of patients. In a study by Vinod dhiman et al,20 77.5% of patients needed final refractive correction of less than 1.5D.Rajeev Kumar et al 14 reported that the number of patients requiring less than 1D correction was the highest(236). 73 patients out of the 105 patients who were prescribed glasses reported symptomatic relief at 1 month follow up.(69.5%).This is similar to the findings of Srimathy A Jain et al 18 who reported symptomatic relief in 69% of patients with refractive errors corrected with spectacles. The limitation of the study is the small hospital based sample size.

A patient with headache presents generally to the ophthalmologist first. It is necessary to do a thorough checkup and check if the patient has any refractive errors. Appropriate correction with spectacles of the refractive errors gives prompt relief of headache and other asthenopic symptoms like eye strain, blurring of vision and heaviness of lids.

1. Lipton RB, Hamelsky SW, Stewart WF. Epidemiology and Impact of Headache. In: Silberstein SD, Lipton RB, Dalessio DJ, Eds. Wolff’s Headache And Other Head Pain, 7th Ed. Oxford: Oxford University Press; 2001:p85- 107 2. Olesen J. Headache classification committee of the International Headache Society (IHS) the international classification of headache disorders, 3rd edition. Cephalalgia. (2018) 38:1–211. 10.1177/0333102417738202 [DOI] [PubMed] [Google Scholar] 3. Stovner, L. J., et al. (2022). The global prevalence of headache: an update, with analysis of the influences of methodological factors on prevalence estimates. The Journal of Headache and Pain, 23(1), 34. https://doi.org/10.1186/s10194-022-01402-2 4. Elena Nguyen, Hilliary Inger, Catherine Jordan, David Rogers,Ocular Causes for Headache,Seminars in PediatricNeurology,Volume40,2021,100925,ISSN1071-9091,https://doi.org/10.1016/j.spen.2021.100925.(https://www.sciencedirect.com/science/article/pii/S107190912100053X) 5. Abrams D, Duke-Elder S. Duke-Elder’s Practice of Refraction. 10th Ed. London: Churchill Livingstone; 1993.P.57-63. 6. Kempen JH, Mitchell P, Lee KE, Tielsch JM, Broman AT. The prevalence of refractive errors among adults in the United States, Western Europe, and Australia. Arch Ophthalmol. 2004; 122: 495-505. 7. Dandona R, Dandona L, Naduvilath TJ, Srinivas M, McCarty CA. Refractive errors in an urban population in southern India: the Andhra Pradesh Eye Disease Study. Invest Ophthalmol Vis Sci. 1999; 40: 2810-2818. 8. Rima M, Dafer, Walter M. Headache and the Eye. Curr O Pin Ophthalmol. 2009; 24:22-8. 9. Wajuihian SO. Exploring Correlations between Headaches and Refractive Errors in an Optometry Clinic Sample. Br Ir Orthopt J. 2024 Jan 3;20(1):1-15. doi: 10.22599/bioj.313. PMID: 38187096; PMCID: PMC10768566. 10. Bellows JG. Headache and the eye.Headache.1968;7:165---170. 11. Griffith, A. The Eyes as a Cause of Headache. Br. Med. J. 1934, 2, 296–297. [Google Scholar] [CrossRef] 12. Supriya N, Dr. (2019). To study the clinical correlation of headache and refractive error subtypes. Journal of Medical Science And clinical Research. 7. 10.18535/jmscr/v7i12.120. 13. Inchara N, Kanthamani K, Shiviji AN. Profile of Ophthalmic Causes of Headache– A Prospective Study. J Clin Biomed Sci 2023; 13(4): 122-125. https://doi.org/ 10.58739/jcbs/v13i4.23.41 14. R Kumar,R Thakur.A prospective study to evaluate the ocular causes of headache ,amongst Patients attending to Ophthalmology out patient department with headache.Int J Acad Med Pharm 2022; 4 (4); 102-105DOI: 10.47009/jamp.2022.4.4.21 15. Marasini S, Khadka J, Sthapit PRK, Sharma R, Nepal BP. Ocular morbidity on headache ruled out of systemic causes—A prevalence study carried out at a community based hospital in Nepal. J Optom. 2012 Apr;5(2):68–74. doi: 10.1016/j.optom.2012.02.007. Epub 2012 Mar 31. PMCID: PMC3860867. 16. Faruqui S, Harne A, Jain R, Agarwal R. A study of the ocular pathology of headache in patients presenting to ophthalmic OPD in a tertiary care center. Kerala J Ophthalmol 2023;35:262-6. 17. Singh, P, Mishal, A and Sunarait, JS. 2021. Ophthalmic causes of headache among patients attending tertiary care center in Kathmandu, Nepal. Nepal Med Coll J, 23(3): 23540. DOI: https://doi.org/10.46889/JOAR.2021.2105 18. Jain S A, Das S, Subashini M, Mahadevan K, Determination of the proportion of refractive errors in patients with primary complaint of headache and the significance of refractive error correction in symptoms relief. Indian J Clin Exp Ophthalmol 2018;4(2):258-262 19. Siddiqui AA, Chaudhary MA, Zafar Ullah M, Hussain M, Ahmed N, Hanif A. Prevalence of refractive errors by age and gender in patients reporting to ophthalmology department. Professional Med J 2020; 27(9):1989-1994. DOI: 10.29309/TPMJ/2020.27.09.5216 20. Vinod Dhiman, Rajeev Tuli, R K Sharma, Sonia, Indu Dhiman. Clinical profile of patients with refractive errors in pre-presbyopic age group in tertiary care centre. MedPulse International Journal of Ophthalmology. August 2019; 11(2): 29-35. https://www.medpulse.in/Ophthlmology/