Age-Related Variations and Seasonal Influences: A Network Analysis of Comorbidities in Asthma Hospitalizations (2013-2023)

Abstract

Background: Asthma, a chronic respiratory disease characterized by airway inflammation and hyperresponsiveness, exhibits significant heterogeneity in its presentation. This study aimed to investigate age-related comorbidity patterns, seasonal variations, and demographic trends among a cohort of asthma patients within a defined geographical region. Methods: A retrospective analysis of 13,695 asthma patients admitted to a Romanian hospital from 2013 to 2023 was conducted. Comorbidity patterns were analyzed using network analysis across age groups, and seasonal trends were investigated through spectral analysis. Results: Asthma admissions exhibited non-linear trends with female predominance (57.72%). The pandemic significantly impacted admission rates, with males experiencing greater COVID-19-related effects. Female admissions showed distinct seasonal patterns potentially linked to domestic responsibilities. Comorbidity patterns evolved with age, shifting from lifestyle factors in younger patients to complex cardiovascular and neurological disorders in older groups. The 60-69 age group showed the highest integration of comorbidity communities. Conclusions: The study revealed that asthma management focus should shift with patient age from the disease itself to addressing underlying comorbidities. Understanding these complex patterns may help personalize treatment strategies and improve long-term prognosis for asthma patients.

Keywords: age-related patterns; asthma; comorbidities; complex network analysis; seasonal variations.

Figure 1

Asthma hospital admissions (2013–2023) showing annual trends and gender differences: (a) annual admission numbers and averages (overall and pre-pandemic); (b) female–male prevalence percentage.

Figure 2

Spectral analysis of seasonal asthma variations using a 12–month periodicity for males and females.

Figure 3

Age distribution and yearly trends: (a) age description histogram and (b) age group yearly variations.

Figure 4

Evolution of asthma comorbidities (using ICD-10 discharge codes) in age groups (a) 18–49; (b) 50–59; (c) 60–69; (d) 70+.

Figure 5

Asthma ICD-10 codes’ community network structures for the 18–49 age group. Subfigures (a–c) represent main, secondary, and communities’ sizes, while (d) colors show the main disorders categories and their relative percentage. (a) PURPLE: smoking (Z72.0, J43.9), oral candidosis (B37.0, B37.1, B37.7!, J31.0), obesity (E11.9, E66.0, G47.32, R73, E78.5), respiratory infections (J15.8, J18.9, J47, J15.9, J15.6, J18.8, B90.9, A15.0, J15.2, J15.1, J15.0), lung fibrosis (J84.1, 9); allergies (J30.4, J30.1). (b) GREEN: urinary disorders (N39.0, N40, N18.90, N20.9, N02.9), sepsis and death (E87.6, A41.9, E87.1, E87.8, I46.9, E86, E87.5, E87.2, E87.0), anemia (D53.9, D64.8, D63.8*, D50.8), respiratory infections (J15.8, J18.9, J47, J15.9, J15.6, J18.8, B90.9, A15.0, J15.2, J15.1, J15.0); COVID-19 (U07.1) (c) BLUE: morbid obesity (E66.9, K76.0).

Figure 6

Asthma ICD-10 codes’ community network structures for the 50–59 age group. Subfigures (a–c) represent main, secondary, and small communities’ sizes, while (d) colours show the main disorders categories and their relative percentage. (a) PURPLE: obesity (E66.0, E78.0, K76.0, R73, E66.9, E11.9, G47.32), candidiasis (B37.0, B37.1, J31.0), urinary (N39.0), allergy (J30.1, J30.4), smoking (Z72.0, J43.9), respiratory infections (J15.8, B90.9, J18.9, Z11.5, J15.9, J47, J12.9, J18.0), COVID-19 (U07.1), psychiatric disorders (F41.2, F06.6, F41.9, F33.9), pulmonary fibrosis (J84.1, J84.9), sepsis (E87.1, E87.6, E87.8, A41.9); anemia (D53.9, D64.9, D50.8). (b) GREEN: chronic pulmonary disorders (ACO) (J96.1, J44.0, J44.1, J44.9, Z99.1, J44.8, J42, J41.0, J94.8, J43.8), pleural disorder (J92.9), cardiovascular disorders (I25.9, I50.0, I27.9, I34.0, E79.0, I11.0, I27.0, I50.9, I47.1, I48, I36.1, I20.9, I45.0, I07.1, I70.0, I20.8, I25.2, I49.3, I30.9, I27.2, I26.9, I70.8, I35.1), obesity complications (E78.2, E78.5, G47.30, E11.8); addition disorders (alcohol and smoking) (F17.2, F10.2). Note: There is no direct causal link established between asymptomatic hyperuricemia and respiratory disorders. The primary concerns with hyperuricemia are related to gout, kidney stones, and other metabolic and cardiovascular issues. (c) BLUE: neuronal disorders (G20, I63.8, I24.9).

Figure 7

Asthma ICD-10 codes’ community network structures for the 60–69 age group. Subfigures (a–c) represent main, secondary, and communities’ sizes, while (d) colours represent the main disorders categories and their relative percentage. (a) PURPLE: moderate-impact cardiovascular disorders (I34.0, I50.9, I36.1, I07.1, I25.2, I35.1, I20.8), death and sepsis (E87.8, E87.1, A41.9, I46.9, E86, E87.6), hepatic disorders (K76.0, R74.0, B18.1, B18.2, E78.0), COVID-19 (U07.1), psychiatric disorders (F41.2, F41.9, F06.6, F33.9); GERD (K21.0, K21.9). (b) GREEN: obesity (E11.9, E66.0, E11.8, G47.32, R73, E78.2, G47.30), advanced cardiovascular disorders (I25.9, I27.9, I48, E79.0, I50.0, I27.0, I11.0, I20.9, I25.5, I70.0, I45.0, I25.8, I49.3, I11.9, I47.1, I27.8, R00.0), oral candidiasis (B37.0, B37.1, J31.0), urinary disorders (N39.0, N18.90, N40, R31), pleural disorders (J90, J92.9), COPD (J44 + Z99.1), lung fibrosis (J84.1, J84.9), respiratory infections (J47, J18.9, J15.8, J15.9, B90.9, J12.9), allergies (J30.4), smoking (Z72.0, F17.2), anemia (D53.9, D64.8, D50.8), lung cancer (C34.9, R59.0); hydro-electrolytic disorders (A41.8, E87.0), (c) BLUE: cataracts (H26.9).

Figure 8

Asthma ICD-10 codes community networks structures for the 70+ age group. Subfigures (a–c) represent main, secondary, and communities’ sizes, while (d) colours represent the main disorders categories and their relative percentage (a) PURPLE: moderate-impact cardiovascular disorders (I34.0, I50.9, I07.1, I35.1, I36.1, I70.0, I27.2, I35.0, I70.8, I26.9, I44.0, I50.1, I45.1, I25.0, I49.8), sepsis and death (E87.6, A41.9, E87.1, E87.8, I46.9, E86, E87.5, E87.2, E87.0), neuronal disorders (G20, G31.0, I63.9, I63.8, R42, I69.3, F03, F06.7); COVID-19 (U07.1) (b) GREEN: moderate-impact cardiovascular disorders (I50.0, I25.9, I27.9, I48, I11.0, E79.0, I44.7, I20.8, I45.0, I70.9, I20.9, I27.0, I25.5, I11.9, I25.2, J12.9, I42.0, I25.6, I49.1, I25.8, I47.1, I35.2, I49.3, I27.8, I20.0, I49.4), oral candidosis (B37.0, B37.1, B37.7!, J31.0), COPD (J44 + Z99.1), lung fibrosis (J84.1, 9), respiratory infections (J15.8, J18.9, J47, J15.9, J15.6, J18.8, B90.9, A15.0, J15.2, J15.1, J15.0), obesity (E11.9, E66.0, G47.32, R73, E78.5), urinary disorders (N39.0, N40, N18.90, N20.9, N02.9), pleural disorders (J92.9, J92.0, J90, J94.8), anemia (D53.9, D64.8, D63.8*, D50.8), allergies (J30.4, J30.1), cancer (C34.9, R59.0, C34.1, C34.8, C34.0), psychiatric disorders (F41.2, F41.9, F06.6, F33.9), smoking (Z72.0, J43.9); ictus and sepsis (E87.1, E87.6, E87.8, A41.9). (c) BLUE: pulmonary metastasis (C78.0).