High-frequency spinal cord stimulation shows improved longer
Spinal cord stimulation (SCS), an FDA-approved therapy for chronic pain, uses paresthesia (low frequency SCS (LF-SCS)) or paresthesia-free (such as high-frequency SCS (HF-SCS)) systems, providing analgesia through partially-elucidated mechanisms, with recent studies indicating a sexual dimorphism in pain pathogenesis. Researchers evaluated SCS therapy sex effects based on paradigm, utilizing visual analog scores (VAS), perceived pain reduction (PPR), and opioid use.

A retrospective cohort study of SCS patients implanted between 2004 and 2020 (n?=?237) was conducted. Descriptive statistics and linear mixed methods analyses were used. HF-SCS (10?kHz) was implanted in 94 patients (40 females, 54 males), and LF-SCS in 143 (70 females, 73 males). At 3?months and 6?months, HF-SCS (p?<?0.001) and LF-SCS (p?<?0.005) had lower VAS scores compared to baseline (p?<?0.005), with no differences across groups. PPR improved in both post-implantation (p?<?0.006) and at 3?months (p?<?0.004 respectively), compared to baseline persisting to 6 (p?<?0.003) and 12?months (p?<?0.01) for HF-SCS, with significantly better PPR for HF-SCS at 3 (p?<?0.008) and 6 (p?<?0.001) months compared to LF-SCS. There were no differences in opioid use from baseline for either modality; however LF-SCS patients used more opioids at every time point (p <?0.05) compared to HF-SCS.

VAS was improved for all modalities in both sexes at 3?months (p =?0.001), which persisted to 6?months (p?<?0.05) for HF-SCS males and females, and LF-SCS females. Female HF-SCS had improved PPR at 3 (p?=?0.016) and 6 (p?=?0.022) months compared to baseline, and at 6 (p?=?0.004) months compared to LF-SCS. Male HF-SCS and LF-SCS had improved PPR post-implantation (p?<?0.05) and at 3?months (p?<?0.05), with HF-SCS having greater benefit at 3 (p?<?0.05) and 6 (p?<?0.05) months. LF-SCS males but not females used less opioids at 6?months (p?=?0.017) compared to baseline; however this effect did not persist.

On linear mixed model analyses, including age, sex and stimulator type, VAS decreased with age, at each timepoint, and had a trend towards increasing with female sex, while PPR increased at 3 and 6?months and lastly HF-SCS was associated with decreased opioid use. PPR at 3 and 6?months improved to a greater extent in HF-SCS. HF-SCS females had improved PPR at 3 and 6?months, and only LF-SCS males used less opioids at 6?months, potentially indicating sex-based pathway.

Source: https://bioelecmed.biomedcentral.com/articles/10.1186/s42234-022-00090-2