Primarily, Genetics (at least one in three suffer from ADHD are from parents with ADHD), Environmental factors during Pregnancy (exposure to certain chemicals), Alcohol & Tobacco use during pregnancy, Premature babies, low birth-weight all are contributing factors.
It's now known that there are at least 8 specific genes that are linked to ADHD. The chromosome bands 16p13 and the genes of the dopaminergic and serotonergic system, including DRD4, SLC6A3 (DAT1) and DBH, are widely implicated to be associated with the susceptibility of ADHD.
Single nucleotide polymorphisms, or SNPs (referred to as “snips”), are the most common type of genetic variation among us. Each SNP represents a difference in a single DNA building block, called a nucleotide. SNPs are quite usual and possibly occur about one in a thousand nucleotides on average. Most of these have no ill effects, not harmful but some of them do. A recent long study concluded that 304 SNPs concentrated in 12 loci, on 11 of the 23 human chromosomes have a significance on ADHD risk.
SNPs that increase risk for ADHD are correlated with the sets of SNPs that put people at risk for depression, learning difficulties, obesity, and other conditions that had been associated with ADHD.
ADHD can only be managed. Currently there are about 33 drugs in use in the Stimulants category (mainly Methylphenidates & Amphetamines) and another 4 drugs in the Non-Stimulants category (mainly Norepinephrine reuptake inhibitors & Alpha agonists) Some of these are short acting and some are long acting upto about 24 hrs. The strength (dosage) and which medication to use has to be determined by the specialist.
