Effects of long-term methylphenidate treatment: a pilot follow-up clinical and SPECT study.
BACKGROUND
Although abnormalities in the regional cerebral blood flow (rCBF) responses to methylphenidate (MPH) treatment have been reported in children with attention deficit hyperactivity disorder (ADHD), there are few prospective longitudinal studies assessing the long-term effects of MPH and discontinuation effects after chronic treatment.


METHODS
The authors studied ten drug-naive children (2 girls, 8 boys, mean age+/-S.D.=9.60+/-1.96) diagnosed with ADHD by the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV) diagnostic criteria, using (99m)Tc-HMPAO-single photon emission computed tomography (SPECT). Patients were studied at baseline (visit 1), after 2 months of MPH treatment (visit 2) and after a drug-free period of 2 months following 12 months of MPH treatment (visit 3) at doses of 1 mg/kg/day. We evaluated SPECT data visually and semi-quantitatively.


RESULTS
Two months of chronic MPH treatment resulted in visually detectable improvement in hypoperfusion in the right frontal cortex and all areas of temporal cortex with the exception of left lateral temporal cortex. This improvement was still detectable on visual evaluations of SPECT data after 2 months of treatment discontinuation. The treatment effects that were detected visually were not statistically significant in semi-quantitative analyses.


CONCLUSIONS
Treatment effects of chronic MPH treatment may persist long after the discontinuation of the treatment.
Akay
Aynur Pekcanlar
AP
Department of Child and Adolescent Psychiatry, Dokuz Eylül University School of Medicine, Izmir, Turkey. pekcanlara@yahoo.com <pekcanlara@yahoo.com>
Kaya
Gamze Capa
GC
Emiroğlu
Neslihan Inal
NI
Aydin
Aysel
A
Monkul
E Serap
ES
Taşçi
Cengiz
C
Miral
Süha
S
Durak
Hatice
H
D001289:Attention Deficit Disorder with Hyperactivity / Q000000981:diagnostic imaging* / Q000188:drug therapy*; D001783:Blood Flow Velocity / Q000187:drug effects / Q000502:physiology; D001931:Brain Mapping; D000697:Central Nervous System Stimulants / Q000627:therapeutic use*; D002648:Child; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008774:Methylphenidate / Q000627:therapeutic use*; D010865:Pilot Projects; D019690:Technetium Tc 99m Exametazime; D013997:Time Factors; D015899:Tomography, Emission-Computed, Single-Photon
D000697:Central Nervous System Stimulants; D008774:Methylphenidate; D019690:Technetium Tc 99m Exametazime