Combinations of
analgesics with
caffeine have been discussed as bearing a risk for
headache chronicity. We investigated whether
aspirin with
caffeine (ASA+) increases
headache frequency compared with
aspirin alone in
migraine,
tension-type headache (TTH), and
migraine + TTH (MigTTH). The population-based German
Headache Consortium Study, which included participants aged 18 to 65 years, collected information about
headache and
analgesics at baseline (2003-2007, t0, response rate: 55.2%), first follow-up after 1.87 ± 0.39 years (t1, 37.2%), and second follow-up after 3.26 ± 0.60 years (t2, 38.8%). We included participants with
headache at t0,
aspirin intake, ASA+ or no
analgesics at t0 and t2, and known
headache frequency. Linear regression was used to estimate changes of
headache frequency (Δt2-t0) and 95% confidence intervals depending on
analgesic intake, stratified by
headache subtypes, adjusting for sex, age,
analgesics at t1, changes of
headache frequency at t1, drinking, smoking, body mass index, education,
headache frequency at t0. Of 509 participants (56.0% women, 42.0 ± 11.8 years [mean ± SD]), 45.2% reported
aspirin intake (41.3 ± 10.9 years, 59.6% women,
headache days at t0: 2.8 ± 3.1 d/mo, t2: 3.6 ± 4.1 d/mo), 11.8% ASA+ intake (46.0 ± 9.8 years, 73.3%, t0: 4.8 ± 6.1 d/mo, t2: 5.3 ± 5.1 d/mo), and 43.0% no
analgesics (41.6 ± 13.1 years, 47.5%, t0: 3.8 ± 6.2 d/mo, t2: 5.3 ± 6.6 d/mo). There was no increase in
headache frequency in participants with ASA+ intake compared with
aspirin (adjusted, all
headache: -0.34 d/mo [95% confidence intervals: -2.50 to 1.82],
migraine: -1.36 d/mo [-4.76 to 2.03], TTH: -0.57 d/mo [-4.97 to 3.84], MigTTH: 2.46 d/mo [-5.19 to 10.10]) or no
analgesics (all
headache: -2.24 d/mo [-4.54 to 0.07],
migraine: -3.77 d/mo [-9.22 to 1.68], TTH: -4.68 d/mo [-9.62 to 0.27]; MigTTH: -3.22 d/mo [-10.16 to 3.71]). In our study, ASA+ intake did not increase
headache frequency compared with
aspirin or no
analgesics.