Obesidad y cefalea

Obesity in Children With Headaches

Headache. 2013;53(6):954-961. © 2013  Blackwell Publishing

Abstract and Introduction

Abstract

Objective
To examine the association between obesity and the different types of primary headaches, and the relation to headache frequency and disability

Background
The association between obesity and headache has been well established in adults, but only a few studies have examined this association in children, in particular, the relationship between obesity and different types of primary headaches.

Methods
 The authors retrospectively evaluated 181 children evaluated for headaches as their primary complaint between 2006 and 2007 in their Pediatric Neurology Clinic. Data regarding age, gender, headache type, frequency, and disability, along with height and weight were collected. Body mass index was calculated, and percentiles were determined for age and sex. Headache type and features were compared among normal weight, at risk for overweight, and overweight children.

Results
A higher prevalence (39.8%) of obesity was found in our study group compared with the general population. The diagnosis of migraine, but not of tension-type headache, was significantly associated with being at risk for overweight (odds ratio [OR] = 2.37, 95% confidence interval 1.21– 4.67, P = .01) or overweight (OR = 2.29, 95% confidence interval 0.95– 5.56, P = .04). A significant independent risk for overweight was present in females with migraine (OR = 4.93, 1.46– 8.61, P = .006). Regardless of headache type, a high body mass index percentile was associated with increased headache frequency and disability, but not with duration of attack.

Conclusions
Obesity and primary headaches in children are associated. Although obesity seems to be a risk factor for migraine more than for tension-type headache, it is associated with increased headache frequency and disability regardless of headache type.

Introduction
Headaches are a common complaint in children and adolescents, with prevalence ranging from 40% to 75%.[1] Similarly, childhood obesity has become a serious public health problem, and increases in obesity rates have been observed in children of all ages.[2, 3] Recent studies indicate that approximately 20% of school-age children in European countries are overweight or obese and 5% are obese. In North America, these figures are 30% and 15%, respectively.[4] In Israel, cross-sectional data from school-based surveys conducted in 1997 and 1998[5] showed that approximately 16– 20% of school children could be classified as overweight or obese (body mass index [BMI] >85th percentile). A higher obesity rate of up to 26% was described in the 2010 Organization for Economic Co-operation and Development (OECD) report.[6]
Chronic headaches in children are associated with school impairment, a decrease in the amount of free time spent with peers or engaging in after-school activities, and other factors that significantly impair quality of life, such as appetite and sleep.[7, 8] Overweight and obese children are at a higher risk for developing chronic diseases such as hypertension, dyslipidemia, diabetes, heart disease, and stroke.[9] Both conditions have also been associated with psychiatric comorbidity; obesity is related most notably to depression, eating disorders especially loss of control over eating, and attention deficit hyperactivity disorder,[10] while children and adolescents with primary headaches were found to suffer more readily from depression, anxiety, and attachment disorders.[11]
The association between obesity and headache has been well established in adults. Population-based studies have found that individuals with episodic headaches who were obese had over 5-fold increased odds of developing chronic daily headaches (CDHs).[12]This association occurred primarily with chronic migraine and not with chronic tension-type headache (TTH).[13] Increased odds of developing migraine-type headaches was found in obese premenopausal women.[14] In patients with migraine, a high BMI was associated with more frequent and severe migraine attacks.[15] Only a few studies have examined this association in children. In a multicenter study by Hershey et al[16] on children with primary headaches, obesity was associated with headache frequency and disability, with significant improvement after weight loss. Similarly, adolescents with recurrent headaches were more overweight and obese than those without headaches.[17] In a recent study by Pinhas-Hamiel et al,[18] overweight adolescent females had an almost 4-fold excess risk of headache when compared with normal-weight girls.The purpose of the present study was to examine the association between obesity and the different types of primary headaches, and the relation to headache frequency and impairment.
The association between obesity and headache has been well established in adults. Population-based studies have found that individuals with episodic headaches who were obese had over 5-fold increased odds of developing chronic daily headaches (CDHs).[12]This association occurred primarily with chronic migraine and not with chronic tension-type headache (TTH).[13] Increased odds of developing migraine-type headaches was found in obese premenopausal women.[14] In patients with migraine, a high BMI was associated with more frequent and severe migraine attacks.[15] Only a few studies have examined this association in children. In a multicenter study by Hershey et al[16] on children with primary headaches, obesity was associated with headache frequency and disability, with significant improvement after weight loss. Similarly, adolescents with recurrent headaches were more overweight and obese than those without headaches.[17] In a recent study by Pinhas-Hamiel et al,[18] overweight adolescent females had an almost 4-fold excess risk of headache when compared with normal-weight girls.The purpose of the present study was to examine the association between obesity and the different types of primary headaches, and the relation to headache frequency and impairment.

Methods
Patients
This retrospective study included children up to 18 years of age who were evaluated for headaches as their primary main complaint between 2006 and 2007. All patients were referred by their primary physician to our Pediatric Neurology Clinic and were identified retrospectively from the clinic database. Children with developmental delay, seizure disorder, major psychiatric disorders, hydrocephalus, or different systemic diseases such as hypertension were excluded from the study.

Chart Review
During their initial and follow-up visits to the Clinic, all patients and parents completed a semistructured history form. The forms and personal interviews focused on the main characteristics of the headaches, including age at onset, location, quality, frequency, duration, aura, associating symptoms, and family history. A headache-related disability was measured using the Pediatric Migraine Disability Assessment (PedMIDAS) questionnaire,[19] a 6-item questionnaire assessing the level of impairment in school, home, and social activities in the previous 3 months. Consumption of medications for acute treatment in the last 3 months was also assessed. All children underwent thorough physical and neurological assessments, and weight and height measurements. Additional blood tests or neuroimaging studies were carried out as required. The final diagnosis of the headache typed was based on 2004 International Classification of Headache Disorders 2nd Edition (ICHD-II) criteria.[20] BMI was calculated as the weight in kilograms divided by the height in meters squared. At risk for overweight was defined as BMI 85th to <95th percentile for age and gender. Overweight was defined as BMI ≥95th percentile for age and gender according to the Centers for Disease Control and Prevention health data.[21] These growth charts have been reported to be appropriate for assessing Israeli children.[22] Children with BMI <5th percentile (n = 7) were defined as underweight and were excluded from the study.
The associations between BMI and headache type, duration, frequency, and disability were assessed.

Statistical Evaluation
Categorical data were summarized as proportions (percentages), and continuous variables as means and standard deviations (SDs). For group comparison, chi-square analysis and Fisher's exact tests were used for qualitative variables, and Student's t-test and Kruskal–Wallis test were used for quantitative variables.Multivariate analyses of the associations between BMI and headache type and disability were conducted using logistic regressions with odds ratio (OR) and 95% confidence interval (CI). Analyses for the total sample were adjusted for age and gender.For all comparisons and analyses, all P values refer to 2-tailed tests. P value of <.05 was used as the cut-off point of statistical significance.The study was approved by an institutional review board committee.

Results
Subject Clinical Features and Headache Diagnosis
The cohort consisted of 181 children aged 4– 18 years (mean 10.14, SD = 3.36), with 81 (44.8%) males and 100 (55.2%) females. Follow up lasted 2.2– 6 years (mean 4.3, SD = 1.26). All children had normal physical and neurological examinations, and unremarkable growth and developmental milestones.The baseline headache diagnosis and subclassifications were made according to the 2004 ICHD-II criteria.[16] A migraine headache, including all subtypes such as migraine with and without aura, chronic and probable migraine, was diagnosed in 44.7% of patients, and a TTH was diagnosed in 48.1%. Thirteen (7%) children had unclassified headaches. Episodic and chronic headaches were not distinguished in separate groups because the numbers of patients within each group were too small to give reasonable interpretations.

BMI and Headache Diagnosis
Of the 181 study participants, 109 (60.2%) were of normal weight, 48 (26.5%) were categorized as at risk for overweight, and 24 (13.3%) as overweight. Overall, 39.8% of the study population had BMI ≥85th percentile. This value is significantly higher than the recent estimates of pediatric obesity rate in Israel 26% (P = .05) reported in the 2010 OECD report.[6] The mean age of children in the 3 weight groups was similar: 10.2 ± 3.08 years, 10.4 ± 3.12 years, and 10.3 ± 2.9 years in the normal, at risk for overweight, and overweight groups, respectively. A significantly greater proportion of females was found in the at risk for overweight (68.8%) and overweight (70.8%) groups compared with the normal-weight group (45.9%, P = .02). The diagnosis of migraine was more common in the at risk for overweight (60.4%) and overweight (62.4%) groups compared with the normal-weight group (34%, P = .01) (Table 1).When adjusted for age and gender, the diagnosis of migraine but not of TTH was significantly associated with being at risk for overweight (OR = 2.37, 95% CI 1.21– 4.67, P = .01) or overweight (OR = 2.29, 95% CI 0.95– 5.56, P = .04). A significant independent risk for overweight was present in females with migraine (OR = 4.93, 1.46– 8.61, P = .006) compared with males (OR = 0.77, 0.41– 4.28, P = .56) (Table 2).

BMI and Headache Frequency and Disability
Patients were subdivided into 3 groups according to attack frequency: (1) 4 or less attacks per month; (2) 5– 15 attacks per month; and (3) more than 15 attacks per month. A high frequency of headaches was associated with obesity. Frequent headaches (more than 15 attacks per month) were significantly more common in the obese children compared with the normal-weight children, 23% vs 12%, P < .01. Headache duration was not significantly different in the 2 groups, lasting less than 2 hours in 35% vs 38% of patients, 2– 4 hours in 55% vs 49%, and longer than 4 hours in 10% vs 13% (P = not significant). When asked, "How many days per month are you using medications for acute headache?" 43% of the obese children vs 17% of the normal-weight children reported using analgesic medications more than 15 days per month (Table 3).
A percentage of children with some level of disability (PedMIDAS grades II-IV) was assessed in relation to BMI and headache type, and adjusted for age and gender (Table 4). For the total study population, 14.7% of those with normal weight had some level of disability compared with 20.3% of the at risk for overweight group (OR = 1.7; CI 1.4– 2.2, P < .001) and 33.3% in the overweight group (OR = 3.1; CI 1.9– 5.8, P < .0001). Similar results were measured for both migraine and TTH. For children with migraine, 12.5% of those with normal weight had some level of disability compared with 17.8% of the at risk for overweight group (OR = 1.9; CI 1.5– 2.4, P < .0001) and 30.7 in the overweight group (OR = 3.7; CI 2.2– 6.1, P < .0001). For children with TTH, 15.2% of those with normal weight had some level of disability compared with 22.2% of the at risk for overweight group (OR = 1.6; CI 1.3– 2.0, P < .0001) and 30% in the overweight group (OR = 2.9; CI 1.7– 4.9, P < .0001).

Discussion
The main findings of the present study are the high rate of obesity in our population of children with primary headaches, and the correlation of BMI percentile to headache diagnosis, frequency, and disability. Overall, 39.8% of the study population had BMI ≥85th percentile (26.5% were categorized as at risk for overweight and 13.3% as overweight). This value is significantly higher than the recent estimates of pediatric obesity rates in Israel 26% (P = .05). These results are similar to some previous adult studies that showed a significant association between BMI >30 and prevalence and incidence of headaches.[12, 23] The results differ, however, from a large multicenter study by Hershey et al[16] that found the same obesity rate in pediatric headache sufferers and the general pediatric population. In another recent study, Pakalnis and Kring[24] evaluated 925 children from their pediatric headache clinic. They found that although obesity seemed to be more prevalent in their series of patients compared with population-based norms, significant differences were noted only in patients with CDH and in the subgroup of chronic TTH.
In our study, the strongest association with obesity was found for females and for children with migraine headache. In the obese group, 59.7% of headaches were reported as migraine, whereas among normal-weight subjects 34.8% had migraine and 54.1% had TTHs. Females with migraine had an almost 5-fold risk for overweight when compared with males. These results are in accordance with other recent studies in adults that found a significant association between obesity and migraine progression and frequency.[25] In a large population study by Bigal et al,[15] obesity was found to be an exacerbating factor for migraine, but not for other types of episodic headache. A high prevalence of migraine was found in obese patients undergoing corrective obesity surgery.[26] Horev et al found a high incidence of migraine with aura in morbidly obese women and suggested high estrogen levels produced by adipose tissue as a possible explanation.[27] Recent studies in children also reported a strong association between overweight and migraine headache.[28, 29] In a recent study of 273 children and adolescents, 50% of obese patients suffered from migraine compared with only 25% in the normal-weight group.[18]
Several possible mechanisms that may account for the association between obesity and frequent migraine have been suggested.[30] Obesity is recognized as a pro-inflammatory state. Markers of inflammation, including leukocyte count, tumor necrosis factor-α, and interleukin-6, increase in obesity and may be associated with neurovascular inflammation in patients with migraine.[31] Plasma calcitonin gene-related peptide levels, an important post-synaptic mediator of trigeminovascular inflammation in migraine, are elevated in obese individuals, particularly in women.[32] Finally, recent data suggest that dismodulation in hypothalamic neuropeptides orexin in obese persons may be associated with increased susceptibility to neurogenic inflammation causing migraine attacks.[30, 33] Information regarding the association between obesity and headache-related disability in children is limited. In his study on 913 children with headache, Hershey et al found a significantly positive correlation between BMI percentile and headache frequency and headache-related disability scores. At follow up, a reduction in BMI was associated with a reduction in headache frequency, but not with headache-related disability.[16] In another recent study on 124 children with migraine, obesity was associated with frequency, but not severity of migraine attacks.[28]
Headache frequency, duration, and disability were considered in trying to assess the headache-related burden in our study. Obese children in our study had a significantly higher rate of very frequent headaches (more than 15 attacks per month) as well as higher disability grades compared with normal-weight children. The association between BMI percentile and higher disability grades was similar for both migraine and TTH. There was no significant difference in duration of attacks between obese and normal-weight children. Additionally, we found a significantly higher rate of acute drug treatment in our patients with obesity compared with normal-weight children, similar for both migraineurs and children with TTH. This may also reflect the more frequent and disabling attacks among the obese children. These results are compatible with prior results in adult studies.[15, 23] In their population study of adults with CDH, Bigal and Lipton found that obese patients not only had a higher rate of headache, but also suffered from increased severity of headaches and missed more school and work days than non-obese patients.[13] It was hypothesized that increased attack frequency may cause neuronal sensitization that reduces response to therapy and that obesity contributed toward the development of this sensitivity. In adults with episodic headaches, obesity was associated with higher disability grades only in patients with migraine, but not in those with other types of episodic headaches.[41]
Some caution is required in assessing the type of relationship between obesity and headache frequency and disability in children. Current data are not sufficient to establish a significant causal relation, and both physiological and environmental factors are probably playing a role. Obesity was found to be associated with increased prevalence and severity of other chronic pain disorders besides headache, such as musculoskeletal and abdominal pain.[35, 36] Both conditions are associated with psychiatric comorbidities, such as depression and anxiety,[10, 37] that can further increase headache frequency and disability.[38] Lifestyle may have an impact on both weight and headache. In a population-based study by Molarius et al,[39] physical inactivity was strongly associated with headache disorders independent of economic and psychosocial factors. On the other hand, recurrent headaches were found to be associated with low physical activity[40] that can further contribute to overweight and further increase headache frequency.[17] Sleep problems such as short sleep duration and poor sleep quality may also play a role in both obesity and recurrent headaches.[41, 42]
No matter what the leading explanations for the correlation between obesity and headaches are, given our evidence as well as others, weight is a modifiable risk factor for recurrent headaches in children. Weight and BMI should be measured and calculated in all children presenting with headache, and weight control should be part of the treatment of chronic headache in children.Some limitations should be considered in the present study. First, our sample cannot be considered as representative of pediatric headache patients because of selection bias. Subjects who are referred to a hospital clinic might have more health-related problems compared with children with headaches treated within the community. Second, stratification of data according to headache diagnosis and gender resulted in relatively small groups that could underpower the analyses. Finally, as mentioned before, we cannot infer causality between obesity and headache frequency and disability.
In summary, our data show a high rate of obesity in children with primary headaches compared with the general population. The strongest association with obesity was found for females and for children with migraine headaches. In all the children with primary headaches, a high BMI percentile was associated with increased headache frequency and disability. Although we were unable to adequately address the question of causal relationship, we believe in and emphasize the importance of obesity prevention and treatment in children with headaches.References

Headache. 2013;53(6):954-961. © 2013  Blackwell Publishing