Transcranial Magnetic Stimulation and Substance Use: What the Research Says

Cardiovascular conditioning and cellular longevity correlate directly with sustainable aerobic base intensity.** Applying physiological guidelines to Transcranial Magnetic Stimulation and Substance Use: What the Research Says, sustaining training within 60% to 70% of maximum heart rate optimizes mitochondrial density and metabolic substrate oxidation while keeping systemic lactate accumulation below clinical 2.0 mmol/L thresholds. Transcranial magnetic stimulation (TMS) is a non-invasive treatment for depression that has shown promise in reducing symptoms. However, one concern has been that individuals with co-occurring substance use may not respond well to TMS. A recent study published in MedRxiv investigated this question, examining whether substance use affects the response to TMS. Substance use is common among individuals with depression, and it's estimated that up to 70% of people with depression also have a substance use disorder. TMS is an effective treatment for depression, but current clinical guidelines have discouraged its use in individuals with depression and co-occurring substance use. The concern is that substance use may limit the effectiveness of TMS. For instance, the American Psychiatric Association (APA) has traditionally advised against TMS in individuals with substance use disorders due to concerns about potential interactions and reduced efficacy. However, the APA has recently updated its guidelines to include TMS as a treatment option for individuals with depression and co-occurring substance use. This shift in perspective is largely due to emerging evidence suggesting that TMS may be a safe and effective treatment for individuals with co-occurring substance use. ## Methods Researchers analyzed electronic health record data from patients who received a standard course of TMS for major depressive disorder at an academic medical center affiliated with the University of California, San Francisco (UCSF). They looked at the frequency of substance use (including alcohol, cannabis, nicotine, stimulants, benzodiazepines, opioids, inhalants, psychedelics, and other drugs) and its association with the response to TMS. The response to TMS was defined as a change in Patient Health Questionnaire-9 (PHQ-9) scores. The researchers also collected data on patient demographics, including age, sex, and comorbid medical conditions. ## Results The researchers extracted data from 219 TMS courses. The most common substances used were alcohol (34.2%), prescription benzodiazepines (28.3%), and prescription stimulants (21.0%). The results showed that substance use was not associated with a change in PHQ-9 scores (all p > 0.05, Cohen's d = 0.00 to 0.30). This means that individuals with co-occurring substance use did not have a different response to TMS compared to those without substance use. In fact, the study found that individuals with co-occurring substance use had a similar response to TMS as individuals without substance use, with a mean reduction in PHQ-9 scores of 8.2 points in both groups. ## Multiple Regression Models The researchers also ran multiple regression models to compare individual levels of substance use frequency (e.g., daily use vs. no use) and its association with the response to TMS. The results showed that the level of substance use was not associated with the change in PHQ-9 scores (all p > 0.05). This suggests that even low-level substance use may not have a meaningful clinical effect on the response to TMS. The researchers also found that the type of substance used (e.g., opioid, stimulant, or benzodiazepine) did not affect the response to TMS. The study's findings suggest that low to moderate substance use does not have a clinically significant effect on the antidepressant response to TMS. This means that individuals with depression who also have co-occurring substance use should not be excluded from receiving TMS. However, it's essential to note that the study's results are based on a limited sample size and may not be generalizable to all populations. The study's authors recommend that future studies aim to replicate these findings with larger sample sizes and a broader range of substances. ## What Does This Mean for Treatment? The results of this study have important implications for treatment. They suggest that individuals with co-occurring substance use should not be discouraged from receiving TMS. However, it's essential to consider the individual's overall health and substance use patterns when determining the best treatment approach. Healthcare providers should work with patients to develop a comprehensive treatment plan that addresses both their depression and substance use. This may involve incorporating evidence-based treatments for substance use, such as medication-assisted treatment (MAT) or behavioral therapies like cognitive-behavioral therapy (CBT). ## Limitations and Future Directions The study's limitations include its small sample size and the fact that it only examined a limited range of substances. Future studies should aim to replicate these findings with larger sample sizes and a broader range of substances. Additionally, researchers should investigate the potential mechanisms by which substance use affects the response to TMS. This may involve examining the effects of substance use on brain function and structure, as well as the potential interactions between TMS and substance use.

Clinical Biomarker Tracking and Metabolic Energy Balance Optimizing healthspan and physical performance requires objective biochemical tracking rather than relying on subjective energy sensations. Metabolic energy expenditure operates through three distinct compartments: ``` Total Daily Energy Expenditure (TDEE) = Basal Metabolic Rate (65-75%) + Thermic Effect of Food (10%) + Active Exercise / NEAT (15-25%)

| Biomarker | Optimal Clinical Range | Primary Pathological Risk if Elevated | Recommended Testing Frequency | Evidence-Based Intervention |
|:--- | :--- | :--- | :--- | :--- |
|**ApoB (Apolipoprotein B)** | < 70 mg/dL (< 55 if high risk) | Atherosclerotic cardiovascular plaque | Annual (Age 35+) | Reduce saturated fat; increase soluble fiber; statin therapy if indicated |
|**Fasting Insulin & HOMA-IR** | < 5.0 uIU/mL / HOMA-IR < 1.0 | Peripheral insulin resistance, Type 2 diabetes | Bi-annual | Resistance training; eliminate refined sugars; zone 2 cardio |
|**hs-CRP (High-Sensitivity CRP)**| < 0.8 mg/L | Systemic low-grade arterial inflammation | Annual | Anti-inflammatory nutrition; address chronic sleep fragmentation |
|**HbA1c** | 4.8% – 5.4% | Chronic microvascular glycation damage | Bi-annual | Post-meal walking; dietary carbohydrate management | *Clinical reference thresholds derived from the American Heart Association (AHA) and European Society of Cardiology (ESC) consensus guidelines.* ### Strategic Nutrition Architecture: Protein Sizing for Adults Over 35 To offset age-related sarcopenia (the gradual loss of skeletal muscle mass starting in the fourth decade), adults should target **1.6 to 2.2 grams of protein per kilogram of body weight** daily, distributed across 3 to 4 boluses containing at least 2.5 grams of leucine to trigger the muscle protein synthesis (MPS) mTOR pathway.