Background and Objectives: Macroeconomic instability, particularly income loss, inflation and unemployment, is increasingly recognized as a psychosocial stressor that may influence both symptom burden and healthcare-seeking behavior. This single-center study investigated the association of income, inflation and unemployment with private-sector hospital visits for primary headache disorders and assessed whether economic stressors were associated with different patterns across demographic groups. Materials and Methods: We conducted a single-center, retrospective, ecological quarterly time-series analysis of hospital visits for primary headache disorders between 2016 and 2024 in a private tertiary care hospital in Turkey. After exclusions, 18,522 eligible hospital-visit records were included and categorized by sex and age (<18, 18–64, and ≥65 years). National data on real gross domestic product (GDP), consumer price index (CPI), unemployment and a COVID-19 period indicator were used. Counts were modeled with log-linked Poisson or negative binomial generalized linear models selected through overdispersion diagnostics, with seasonal controls and HAC-robust inference. Results: In most groups, higher GDP was associated with more primary headache visits, whereas higher inflation was consistently associated with fewer visits. The association with unemployment was heterogeneous: visits decreased significantly among the working-age population but increased among older adults. Contemporaneous models outperformed one-quarter lagged alternatives, suggesting that private-sector healthcare seeking may change within the same quarter as macroeconomic shocks. Conclusions: In this private hospital setting, macroeconomic deterioration was associated with reduced primary headache visits, particularly among working-age patients. These findings suggest that financial constraints may suppress private-sector healthcare utilization despite possible increases in stress-related symptoms, and that private hospital data may underestimate headache-related healthcare need during economic crises.

The aim of this study is to investigate the relationship between oil consumption and income in Turkey, using annual data from 1961 to 2016. The stationarity properties of the series are analyzed with Lee and Strazicizh (2003), unit root test allowing for two structural breaks, along with the conventional unit root tests namely ADF, PP and KPSS. Due to conflicting findings of the unit root tests, ARDL bounds test approach to cointegration is used to capture the relationship between oil consumption and income. The findings of the ARDL bounds test indicated that oil and income are cointegrated. The causal relationship between the variables is also examined by employing Toda and Yamamoto (1995), approach to Granger non-causality. The outcomes of the Toda and Yamamoto (1995), procedure showed that the direction of the causality is running from real GDP to oil consumption, but not vice versa. Both bounds test and Toda and Yamamoto (1995), test results reveal that, energy conservation policies will not harm economic growth in Turkey.

Background and Objectives: Spinal infections represent a heterogeneous group of diseases where primary or secondary etiological classification is fundamental for diagnosis and clinical decision-making. The aim is to present multicenter data evaluating etiological patterns associated with comorbidity. This study investigated the etiological distribution of spinal infections in a multicenter cohort and examined the relationships between chronic kidney disease (CKD) and diabetes mellitus (DM) and primary and secondary spinal infection etiologies, which emerged in the study and are thought to contribute to the literature. Materials and Methods: For this early-phase exploratory modelling study, a ridge-penalized logistic regression (L2) model was trained using repeated nested cross-validation (outer 5-fold stratified CV ×10 repetitions; inner 5-fold CV) to generate out-of-fold (OOF) probabilities. The penalty parameter (C) was optimized by minimizing log-loss. All preprocessing was performed within the CV pipeline to prevent data leakage. A supplementary Firth-penalized analysis was conducted as a plausibility check, using the CKD0/DM0 group as reference. Results: The model demonstrated effective discrimination between spinal infection probabilistic profiles (OOF AUC 0.762; conditional OOF bootstrap 95% CI 0.608–0.885). A contrasting probabilistic profile concordance was observed: DM-only patients had a high likelihood of secondary infection (observed secondary risk 93.3%; mean OOF estimated probability 84.4%), compared to a higher likelihood of primary infection in CKD-only patients (observed secondary risk 15.4%, which translates to a primary risk of 84.6%; mean OOF estimated probability 21.8%). Calibration was near-ideal (intercept 0.069; slope 1.028). Decision curve analysis showed a clear utility between the thresholds of 0.15 and 0.84. There were no CKD+DM+ cases (n = 0); analyses were restricted to supported strata. Conclusions: In this multicenter analysis of spine infections, CKD was predominantly related to primary spine infection etiology, whereas DM was more frequently related to secondary spine infections. These findings emphasize the potential role of comorbidity profiles in etiologic classification and need to be confirmed in larger multicenter cohorts.

Background /Objectives: Lumbar spondylosis is a degenerative disorder that may require decompression and stabilization surgery. Rigid titanium rods provide strong fixation, whereas polyetheretherketone (PEEK) rods have been proposed to offer a more flexible load distribution profile. This study compared the radiological outcomes after PEEK versus rigid rod stabilization and evaluated whether the preoperative degenerative findings contributed independently to the postoperative adjacent segment radiological status. Methods: A retrospective cohort of 106 patients undergoing lumbar decompression and posterior stabilization (2020–2025) was analyzed. Rod allocation followed routine clinical practice rather than randomization. Radiological parameters (foraminal area, canal diameter, disc height, and facet volume) were measured preoperatively and at one year postoperatively. Baseline-adjusted ANCOVA models with HC3 robust inference compared PEEK and rigid rods across the two-, three-, and four-segment constructs. Additional models assessed the independent effects of preoperative facet effusion and Modic changes. Results: PEEK rods were associated with the statistically reliable preservation of spinal canal diameter, foraminal area, disc height (particularly in the three- and four-segment constructs), and reduced facet joint volume increase compared with rigid rods after multiple-comparison correction. The findings for the two-segment constructs were less consistent and partly influence-sensitive. Preoperative facet effusion and Modic changes showed no statistically reliable independent association with postoperative radiological outcomes after adjustment. Conclusions: PEEK rod systems were associated with favorable baseline-adjusted radiological preservation patterns, especially in long-segment stabilization. These findings should be interpreted as radiological associations rather than proof of clinical superiority or causal reduction in adjacent segment disease, because rod allocation was nonrandom and clinical, and fusion-related outcomes were not assessed.