Adolescent Hypertension and Stroke in Young Adulthood

In This Article

Abstract and Introduction

Abstract

Background: Adult hypertension is a well-established risk factor for stroke in young adults (aged <55 years), and the effects are even more deleterious than at an older age. However, data are limited regarding the association between adolescent hypertension and the risk of stroke in young adulthood.

Methods: A nationwide, retrospective cohort study of adolescents (aged 16–19 years) who were medically evaluated before compulsory military service in Israel during 1985 to 2013. For each candidate for service, hypertension was designated after constructed screening, and the diagnosis was confirmed through a comprehensive workup process. The primary outcome was ischemic and hemorrhagic stroke incidence as registered at the national stroke registry. Cox proportional-hazards models were used. We conducted sensitivity analyses by excluding people with a diabetes diagnosis at adolescence or a new diabetes diagnosis during the follow-up period, analysis of adolescents with overweight, and adolescents with baseline unimpaired health status.

Results: The final sample included 1 900 384 adolescents (58% men; median age, 17.3 years). In total, 1474 (0.08%) incidences of stroke (1236 [84%] ischemic) were recorded, at a median age of 43 (interquartile range, 38–47) years. Of these, 18 (0.35%) occurred among the 5221 people with a history of adolescent hypertension. The latter population had a hazard ratio of 2.4 (95% CI, 1.5–3.9) for incident stroke after adjustment for body mass index and baseline sociodemographic factors. Further adjustment for diabetes status yielded a hazard ratio of 2.1 (1.3–3.5). We found similar results when the outcome was ischemic stroke with a hazard ratio of 2.0 (1.2–3.5). Sensitivity analyses for overall stroke, and ischemic stroke only, yielded consistent findings.

Conclusions: Adolescent hypertension is associated with an increased risk of stroke, particularly ischemic stroke, in young adulthood.

Graphic Abstract: A graphic abstract is available for this article.

Introduction

The prevalence of adolescent hypertension is on the rise, with a 75% increase over the last 2 decades.^[1] This is related mainly to the global obesity pandemic.^[1,2] Several studies have described links between adolescent hypertension, future renal injury (3), and cardiovascular mortality.^[3]

Stroke is the second leading cause of death worldwide and the main cause of disability in adults.^[4] Moreover, the occurrence of stroke in younger adults carries an exceptionally high disease burden due to its potential for lifelong disability.^[5] Among adults, hypertension was the most common modifiable risk factor for stroke.^[4] However, data are scarce on the role of adolescent hypertension as a risk factor for future stroke, and it is unclear whether such association is independent of adolescent body mass index (BMI).

In previous works based on a nationwide cohort of adolescents who underwent screening for blood pressure (BP), we demonstrated associations of adolescent hypertension with higher risks for future type 2 diabetes,^[6] early- and end-stage renal disease,^[7,8] and cardiovascular mortality.^[9] Here we studied the association between adolescent hypertension and incident stroke in young adulthood.

Table. Baseline Characteristics of the Study Population According to Hypertension Status in Adolescence
	Without hypertension (n=1 895 166)	With hypertension (n=5221)	P value
Men, n (percentage of all)	1 090 759 (57.6)	4792 (91.8)	<0.001
Age, y	17.3±0.5	17.6±0.6	<0.001
BMI, kg/m²	21.4±3.6	26.6±5.6	<0.001
Weight status, n (%)			<0.001
Underweight	125 337 (6.6)	103 (2.0)
Normal BMI	1 495 129 (78.9)	2205 (42.2)
Overweight	181 791 (9.6)	1027 (19.7)
Obesity	92 900 (4.9)	1886 (36.1)
Residential socioeconomic status, n (%)			0.071
Low	487 898 (25.9)	1364 (26.2)
Medium	988 491 (52.5)	2790 (53.7)
High	405 168 (21.5)	1044 (20.1)
Cognitive score, n (%)			0.003
Low	335 207 (17.8)	888 (17.1)
Medium	1 316 128 (69.9)	3587 (69.1)
High	230 307 (12.2)	716 (13.8)
Education of ≥11 y, n (%)	1 769 786 (93.6)	4897 (93.9) <0.001
Israeli born, n (%)	1 593 451 (84.1)	3960 (75.8)	<0.001
Systolic BP, mm Hg	116.2±12.3	143.3±14.2	<0.001
Diastolic BP, mm Hg	71.4±8.3	82.5±9.7	<0.001
Unimpaired health, n (%)	1 330 961 (70.2)	2434 (46.6)	<0.001
Diabetes, n (%)	25 524 (1.3)	300 (5.7)	<0.001

For continuous variables, the mean±SD is given unless specified otherwise. BMI was classified according to age- and sex-matched percentiles based on criteria of the US Center for Disease Control and Prevention: BMI<5th percentile (underweight), 5th≤BMI<85th percentiles (normal BMI), 85th≤BMI<94th percentiles (overweight), and 95th percentile≤BMI (obesity). The systolic and diastolic BPs are the first measurements made during the first physical examination in the conscription center. The diabetes status provided is the status until the end of the follow-up period, rather than only at baseline. Baseline characteristics between the groups were compared using the χ2 test for categorical variables, Mann-Whitney U test for ordinal variables, and Student t test for continuous variables. The number of individuals with at least 1 missing value was 24 361 (1.3%). Missing values by variables; residential socioeconomic status, 13 623 (0.7%); cognitive score, 13 545 (0.7%); years of education, 4295 (0.2%). BMI indicates body mass index; and BP, blood pressure.