Primary headache disorders in the adult general population of Pakistan—a cross sectional nationwide prevalence survey

DOI: https://doi.org/10.1186/s10194- 017- 0734- 1

Abstract-Summary The large geographical gaps in our knowledge of the prevalence and burden of headache disorders include almost all of Eastern Mediterranean Region (EMR).

One adult member (18–65 years) of each household, also randomly selected, was interviewed by a trained non-medical interviewer from the same location using a previously-validated structured questionnaire translated into Urdu, the national language.

We estimated 1-year prevalences of the headache disorders of public-health importance and examined their associations with demographic variables using mul- tivariate analysis.

There were 4223 participants (mean age 34.4 ± 11.0 years; male 1957 [46.3%],

female 2266 [53.7%]; urban 1443 [34.2%], rural 2780 [65.8%]).

Headache in the previous year was reported by 3233 (76.6% [95% CI:

75.3–77.8%]).

The age- and gender-adjusted 1-year prevalence of migraine was 22.5% [21.2–23.8%] (male 18.0% [16.8–19.2%], female 26.9% [25.6–28.2%]), of tension- type headache (TTH) 44.6% [43.1–46.1%] (male 51.2% [49.7–52.7%], female 37.9% [36.4–39.4%]), of probable medication-overuse headache 0.7% [0.5–1.0%] (male 0.7% [0.5–1.0%], female 0.8% [0.5–1.1%]) and of other headache on ≥15  days/month 7.4% [6.6–8.2%] (male 4.4% [3.8–5.0%], female 10.4% [9.5–11.3%]).

Migraine was more prevalent in females by a factor of 3:2 although this associa-

tion barely survived (p = 0.039) after correcting for other factors.

All headache and migraine were age-related, peaking in the age group

40–49 years; TTH peaked a decade earlier.

With three quarters of its population affected, headache disorders must be on the

public-health agenda of Pakistan.

Extended: Migraine was more prevalent in females in a ratio of 3:2 (p < 0.001), pMOH and other headache on ≥15 days/month about two-fold (the latter signifi- cantly [p < 0.001] but the former not).

Burden data will be reported in a future publication.

Background Headache disorders affect almost half the world’s population, according to a survey of the published literature conducted nine years ago [89].

Tension-type headache (TTH) and migraine are the major contributors in terms of prevalence, being the second and third most common disorders in the world [31]. Large geographical gaps in our knowledge of the prevalence and burden of head-

ache disorders have been evident from the various surveys [31, 89–91].

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1 Public Health

In the Eastern Mediterranean Region is another large geographical knowledge gap; the countries include Pakistan, with the sixth largest population in the world [92] and characterised by economic and political instability and, in parts, by geo- graphical inaccessibility.

Its two purposes were to contribute to knowledge of the global burden of head-

ache [32] and to provide evidence for national health policy in Pakistan.

Methods This questionnaire, used in similar studies conducted in other countries [50], included demographic enquiry, screening and diagnostic questions for headache.

Diagnoses were not made by the interviewers, but subsequently by diagnostic algorithm [50], applied to the most bothersome headache if a participant reported more than one type of headache.

In calculating this we assumed a headache prevalence of 50% and applied a con-

fidence level of 99% and confidence interval (CI) of 2%.

We calculated headache prevalences as percentages with 95% CIs. We performed bivariate analyses, calculating odds ratios (ORs) with 95% CIs, to look for associations between headache types (migraine, TTH or all headache on ≥15 days/month) and demographic variables.

In subsequent multivariate logistic regression analyses, we calculated Exp(B) with 95% CIs taking prevalence of each headache type as the dependent variable and gender, age, marital status, habitation, education level, income, province and BMI as factors.

Results TTH was by far the most prevalent headache disorder (44.7%), but migraine was also very common, reported by over one fifth (22.9%) of participants.

Migraine was more prevalent in females in a ratio of 3:2 (p < 0.001), pMOH and other headache on ≥15  days/month about two-fold (the latter significantly [p < 0.001] but the former not).

Participants who were divorced, widowed or separated also had more headache (OR = 1.9), migraine (OR = 1.8) and headache on ≥15 days/month (OR = 2.5), but less TTH (OR = 0.7) than single participants.

Age 40–49 years remained positively associated with migraine, and an associa- tion emerged with headache on >15 days/month, while ages 30–49 were positively associated with TTH.

Being poor remained strongly associated with both migraine and headache on

≥15 days/month, but the negative association with TTH did not survive. Discussion Very similar findings have emerged from India, a country which shares Pakistan’s genetic, environmental and cultural composition: the 1-year prevalence in Karnataka State of all headache was 63.9%, of migraine 25.2% (with a 4:3 female preponder- ance) and of TTH 35.1% [93].

1.1

Epidemiology

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The prevalence in Pakistan of all causes of headache on ≥15 days/month (8.1%) is approaching three times the estimated global average of 3% [89], but still not outside the range found by similar studies.

Speculatively, the same may have occurred, to a greater degree, with TTH, a disorder perhaps more easily hidden than migraine: in contrast to most studies else- where, we found in Pakistan a significantly higher prevalence of TTH in males (51.2%) than in females (37.9%), although this difference, with Exp(B) = 0.8, was also barely significant (p = 0.026) after correction for other factors.

Conclusion With over three quarters of its population affected, headache disorders must be on the public-health agenda of Pakistan.

Worldwide, these disorders are the third leading cause of disability [91]; infor- mation from specific enquiry into the burden attributable to headache disorders in this country is needed to inform health policy and priority-setting, and will be reported soon.

Acknowledgement A machine generated summary based on the work of Herekar, A. A.; Ahmad, A.; Uqaili, U. L.; Ahmed, B.; Effendi, J.; Alvi, S. Z.; Shahab, M. A.; Javed, U.; Herekar, A. D.; Khanani, Rafiq; Steiner, T. J. 2017 in The Journal of Headache and Pain.

The prevalence of primary headache disorders in Saudi Arabia: a cross- sectional population-based study